# User:Phol ende wodan/Quest level redesign

Contents

1 Archeologist
2 Barbarian
3 Caveman
4 Healer
5 Knight
6 Monk
7 Priest
8 Ranger
9 Rogue
10 Samurai
11 Tourist
12 Valkyrie
13 Wizard
14 Other notes
15 Nice and necessary changes

This is a proposal to modify the levels of the various Quests to make them more thematic and less bland and boring. The current Quests don't really emphasize this very much in their level design.
Currently most of the interesting portions of the Quest are the home, locate, and goal special levels, as well as the specialized set of monsters that occupy the branch. But the filler levels in particular tend to be either boring cavern levels, boring cavern-fill-with-water-or-lava levels, or boring room-and-corridor levels, and about eleven of the thirteen quests finish in some sort of cave or underground building. Ideally, every quest's filler levels would use unique generation algorithms, or algorithms with parameters that can be tuned to generate sufficiently distinct levels.
Additionally, the Quest seems to use the concept of the downstair somewhat oddly; it makes most of the quests seem like they consist of descending into the basement of whatever structure is on the home level. No quest is actually flavored like this. The downstair is, of course, necessary to make level traversals work, but since the player can't use the downstair until given the Quest anyway, there's no particular reason it needs to be contained inside a structure.
This proposal will also take the opportunity to revise the special levels as appropriate to remove annoyances, such as the infamous Ranger home level. It will additionally make minor changes to quest flavor or narrative where appropriate if the levels could be more compelling that way.
The goal here is not a full Quest overhaul, so things like leaders, nemeses, and artifacts will not really be covered. This assumes that none of those will be changing; perhaps the quests could become even more unique and varied if I used the freedom to change any of this, but the scope of this proposal is large enough as it is.
2022 note: I'm currently redesigning one role's Quest in every xNetHack version, with the goal of eventually completing all of them. In general, I'm going beyond what's in this proposal and taking the approach of trying to tell a unique story with each Quest. Leaders, nemeses, artifacts, and even the win conditions and other mechanics of the quest are all on the table in order to avoid different roles' quests feeling the same. Much of it is guided by this document, though; the rest of this page is left as is in the original proposal.

Archeologist
The Archeologist special levels are nothing particularly amazing, but they are pretty good. Given the ridiculously low stakes of the quest (oh no, budget cuts!), I'm not sure why the College of Archeology is a fancy building in a big field that has a moat with dangerous sea monsters in it. The level could be redesigned to fit a college-type setting better, with other buildings, walkways, trees and maybe a fountain or two. Since the quest does not take place in the College of Archeology's basement, the downstairs will be placed somewhere on the left edge of the map, opposite the portal (or else the right edge and the portal will be placed on the left edge).
The upper filler levels consist of the Archeologist on a trek to get to the Tomb of the Toltec Kings. As such, the current room-and-corridor levels make no sense; the player isn't going through a dungeon to get there, they are walking across the surface. Therefore, these levels should be changed to resemble a jungle, with many trees, swampy areas of water and sea monsters, and probably some boulders and rock outcroppings. Possibly dead branches, in the form of +0 quarterstaffs, could be scattered about, which would provide extra hiding places for the many snakes. Stairs should be on opposite ends of the map. These levels should pregenerate with jungle-type monsters like snakes (various kinds including pythons), jaguars, tigers, lynxes, crocodiles, eels, etc.
The Tomb of the Toltec Kings is a pretty good level, but suffers from appearing like a square building in a big open field. If it was intended to be some sort of a step pyramid, it doesn't act like one, because you can't see inside as one would expect to be able to look up a pyramid's slope. NetHack lacks the terrain types and concept of height to make a realistic pyramid, so perhaps it should just be reshaped into a tomb entrance carved out of a mountainside on one end of the map, with the upstairs being on the other edge, and the jungle terrain persisting until tapering off near the entrance. There are some well-ordered human or clay golem statues outside, and some more statues inside. Inside the tomb are all the nasty traps one would expect to find in such a place, and the pits and spiked pits outside remain. Something else that is unnecessary but neat would be making small crypt rooms with human mummies (the Toltec Kings themselves).
Now the Archeologist is actually descending into a tomb, so the downward direction makes sense again. Room-and-corridor levels do work, to some extent, but ideally this would use a new "tomb" filler level generator which generates adjoining non-rectangular rooms with short or no corridors, heavily biases towards secret doors instead of ordinary ones (it'd be neat if you had to come back with the Orb of Detection and use its powers to find all the nooks and crannies you missed), and places lots and lots of traps. Several bats are pregenerated in these levels, a fair bit of loot biased towards gold and gems instead of items, and probably several (sleeping) mummies as well.
The Crypt is fine as levels go, but lacks something in that large portions of it aren't really necessary and it only takes about 20 steps to reach the Minion of Huhetotl. It could be enlarged and reshaped to be less radial (though a sunlike shape of the starting room would be cool). The easiest solution would probably be to randomize the location of him and the altar, but adding in more interesting traps, treasure (because how can an archeological expedition not have lots of gold, gems, and ancient artefacts to loot?) and mummies is also something that could work.
Later on I had another idea for a better direction to take the quest storyline in (while the above is an improvement, it still follows the same bland quest pattern as all the others). Instead, pattern the story after Raiders of the Lost Ark: the College of Archeology is not in any danger and does not contain any enemies (perhaps not even any hostile spawns); Lord Carnarvon's quest hook is that they've discovered that a rival team of ruthless archeologists has located the quest artifact (probably no longer the Orb of Detection) and is after it. The rival team is better-funded, more numerous, and won't hesitate to kill you (though their leader, the new quest nemesis, might have some lines offering for you to join them instead). You must retrieve the artifact before they can get away with it.

Barbarian
The Barbarian quest contains a single upper filler level - an empty plain spanning the whole map - and standard caverns for lower filler levels. The feel of these levels is sort of empty plain without much vegetation, which means that in general there should not be as much of an impetus to fill them with stuff.
The Camp of the Duali Tribe is pretty good, except that of course the downstair should be moved to the left edge of the map. The trees on the right side of the map should be made more sparse so that there are only five or six of them. The somehow magically-not-filled-with-water spiked pit interrupting the river will be replaced by a normal water space, and several boulders will be generated on the right side of the level which can be used to cross. The outbuildings should be a bit more scattered than they currently are, some of the quest friendlies should be placed there, and none of the structures should have doors, because this is a camp.
The upper filler level is supposed to be a desert, so its openness fits. The stairs, of course, should be restricted to be placed on opposite edges of the level. Maybe some rock outcroppings or boulders could be placed here, but it's not very important. However, there is not much of a reason for it to be dark that I can see, so it should be made lit up again.
The left side of the Duali Oasis is pretty much fine, except there should not be land bridges connecting the island to the opposite shores. It's sufficient to make a "ford" where the river gets broken up enough to walk across either above or below the island, and put two or three trees on the island. (Shallow water would be nice here, as well.) The river is moved to the right until it becomes the centerpiece of the level, and the various outbuildings are circled around the island. They generate with doors open. The big hall with the items in the storerooms is still on the right side of the river, and contains two normal open doors on either end. The rest of the quest is fairly sparse in loot, so perhaps the storerooms here should get some additional loot. Some of the ogres and trolls could be placed in the outbuildings. The rock on the far side of the level is removed, with just the downstairs on the right edge.
Lower filler levels are savannah levels, which is basically the same desert + outcroppings + boulders, with a very few scattered trees, with stairs on left and right edges of the map as usual. (If grass terrain is added, the floor should be grass, as well.) These levels could be dark unlike the upper filler; this could be flavored in the locate level entry text as being during sunset.
The goal level continues the savannah filler theme, but Thoth Amon is in a tight cluster of small buildings on the far right side of the map, standing on a cross-aligned altar as before. The buildings are ruined and have doorways without doors. The exact arrangement of these buildings is not important, except that Thoth Amon is not visible until you get pretty close to him. When he sees you he will attack immediately. There are no monsters in the buildings nor around their far side; the buildings are instead fairly heavily trapped. Should you become trapped, Thoth Amon will also wake up and attack.

Caveman
The Caves of the Ancestors have a similar minor problem as other cavern special levels: there is a fair amount of dead space that is not important to traversing the level, unless some desirable item generated there. Other than that, the main logistical problem with the level is that the stairs take you even deeper into the caves, while clearly they are not the same caves as the Dragon's Lair. Shaman Karnov's recounting of the attack and other quest text indicates that the Dragon herself attacked from outside, and then retreated with the Sceptre of Might to her own cave somewhere else. Therefore, part of the right side of the home level should actually be outside the Caves, with the magic portal placed in an antechamber near the entrance, and the stairs should be on the open right edge of the map, meaning you have to go into the Caves to be assigned the quest and come back out again to go to the next level. Parts of the caves may need to be shifted around since the current chambers on the left and bottom will not have any use anymore. And the diagonal choke point should be abolished forever.
Because you have to move from one cave to the next, the upper filler levels should be mostly open. The type of terrain here could really be anything - trees, water, ice, clouds, rocks - as long as it's sufficiently wilderness. A good suggestion by someone was to make these levels heavy snowstorm - moving clouds, ice, little vegetation, low visibility - based on the Cro-Magnon climate.
Similarly, the Dragon's Lair should be a large cave entrance with an open left side of the level tapering down to it, not a full-level cave system. Its narrow corridors should be widened a bit and the pathway to the downstairs should be fairly straight, because as the quest text states, this is how the gigantic Chromatic Dragon travels to and from her lair. The secret door makes no sense and should be removed. A bugbear corpse or two (carrion) and some semipermanent and burnt engravings of things like "----" and "///" and "\|/" (claw and burn marks) scattered along this route might not be out of place. The dead space in the caverns should, again, be cut back on or given something interesting.
Like the Barbarian, the trek through the lower filler levels is just a descent into a nondescript cave for the most part, so cavern fill works here but doesn't really have any strong flavor. More carrion and burn marks are probably good to have, but the level overall still seems bland.
Tiamat's Chamber is fine; you can't really go wrong with a large open area here for a boss fight. The hexagon is a little odd for a dragon's lair because it's such a regular shape, but it doesn't seem like much of a problem. Tiamat herself should perhaps not speak, being a dragon, when the other dragons in the game can't speak.

Healer
The Temple of Epidaurus is mostly fine, but the building should probably be enlarged a bit to make its silly tiny 1-wide rooms at least 2-wide. As always, the downstair should be at the edge of the level, probably opposite the magic portal.
The Healer quest's filler levels suffer not so much from blandness as they do from lack of individuality. The swamp fill used (actually cavern fill that uses water instead of rock) is duplicated in the Knight and the Samurai quests, and doesn't have much relating it to the Healer and their mission. It's a pity there's no real feature for ruins, since bits of stonework and broken arches and pillars and things like that seem like they would be pretty thematic here. Since wall fragments are the best we have right now, perhaps it could be populated with some of those, using the REPLACE_TERRAIN command with low probability (also, this could be done on all the levels of this quest). This would break up lines of sight and possibly make it marginally more interesting than levitating or walking directly over to the downstairs once all the monsters are taken care of. Trees could also be used for this purpose. It would be great if there could be some other obvious terrain indicating pollution or disease on the levels, but such terrain does not currently exist. (Some of the random items on the levels could be replaced by guaranteed potions of sickness, which is not much but it's something.)
The Temple of Coeus is not very important, and its main effect is to guarantee a priest for Healers to donate gold to; the building itself could do with being a little less regular and not have a pointless antechamber with secret doors. The level's name seems a bit odd, since Coeus is not mentioned at all and the actual temple is to the chaotic god Poseidon. If it were made more Poseidon-themed, sea monsters and water elementals could be the predominant monsters on the level. The temple should be more open than it is now, and the stairs should go on opposite ends of the level, instead of descending into the basement of the Temple. But the larger problem is this doesn't really feel like a locate level; it doesn't have all that much Quest significance, and doesn't serve as a clear halfway point of the quest.
The lower filler levels are much the same as the upper ones, and have a similar problem to what is mentioned above: since the locate level doesn't really represent a midpoint, it's hard for these levels to find their identity as a more dangerous version of the upper filler, and consequently it's hard to determine how they should differ.
The Isle of the Cyclops does not have that much of a challenge if all you want to do is kill the Cyclops and retrieve the Staff, since the Cyclops is not asleep and will pick it up and warp to you within a few turns. You don't even have to move anywhere. The Cyclops could be generated asleep and placed in some buildings, but that doesn't really add anything either. Since he's supposed to be using the power of the Staff to draw the life out of everything else nearby, the level should ideally reflect this. Maybe he's got prison cells with quest friendlies behind the bars, or something. A special rule of this level (which may be better paired with Staff balance changes that trade away its level-drain effect for something else): your natural HP regeneration does not work on this level, and you constantly lose 1 HP per turn, as long as the Cyclops is alive and has the Staff.
Insofar as quest monsters go, they are pretty bland. The dragons seem out of place, and should probably be cut down or removed (unless there is some strong flavor reason for putting dragons in this quest that I am not aware of), and while there is an obvious attempt to include poisonous monsters like snakes and rats, poison is never a threat to the Healer. Better would be if there were a common monster with a disease attack, and this monster were made predominant on the levels instead of unthreatening giant rats.

Knight
Camelot Castle is fine, but its long 1-wide corridors should probably be widened, and the stairs should definitely be moved out of the castle to one end of the map. Perhaps it chould be changed to accommodate more trappings of a medieval castle: a moat, (open) drawbridge, gatehouse, and courtyard with a fountain (in case the Knight wants to get Excalibur here); it could also be made less of a boring rectangle than it currently is. The surrounding empty field is pretty boring, and should get something interesting, possibly hallmarks of the battle with Ixoth that recently happened here, like knight and quasit corpses. Due to the next levels being water-themed, the terrain on the edge of the map with the stairs should probably have some scattered water in it.
Upper filler levels are identical to the Healer filler levels, and similarly lack identity. There should probably be some scattered carrion and random burn marks on the floor similar to in the Caveman quest. They should actually perhaps not be water levels, but land instead, with the first water being the Isle of Glass.
The Isle of Glass is fine, but it goes overboard with the number of magic traps. If the goal here is to block all land-based access to the island with magic traps, more water should be added instead. Of course, the downstair should not be smack in the center of the island since the quest does not go beneath the island, though it would be nice if you were still forced to cross through the temple on your way. Possibly, since the isle is a steep rocky summit, it could be a rough oblong shape with walls around the base and containing the temple inside, though this would probably make it feel like a cave. Since you are supposed to "locate" the downstairs when you climb the Isle, maybe the downstairs could be generated/revealed only when you reach the shrine area. As a very unnecessary pun, perhaps some pieces of glass could be scattered around the level or the island.
Another possible way to take the locate level (and slightly change the flavor of the quest) is to replace the Isle of Glass with a fortress of traitor knights (possibly led by Mordred?) you must get through, who are allied with Ixoth. 
Lower filler levels similarly need something to distinguish them from other water-cavern fill levels, but NetHack probably does not have the terrain or objects for this. This part of the Quest is flavored as crossing a body of water or swampland to reach the Dragon's Lair; a pure water level with few scattered islands might actually be better here, requiring levitation or flight in order to reach the goal level. If new terrain types could be added, importing UnNetHack's muddy swamp terrain or some other sort of less-than-solid ground terrain could be added.
The Dragon's Lair has the feel of a rough-hewn cavern occupied by a dragon and his hoard, and works very well, especially since Ixoth does not automatically sense you and run towards the cavern entrance. Similarly to the Chromatic Dragon, the cave should have claw and burn marks and carrion (maybe knight player monster corpses?) scattered around. Ixoth could potentially be placed a little farther back into his pocket of the cavern, and the hoard could be given some guaranteed piles of gold (because come on, he's a dragon), but overall this is a good level. Similar to the other non-humanoid nemeses, he should probably not speak, only roar and take angrily-flavored actions. (Though it could be decided that dragons can speak but the common ones prefer not to, or the nemesis dragons are in a class by themselves, or something.)
I would expect that if any quest generates dragons as a lesser monster, it would be this quest; perhaps one per level. Perhaps only red dragons, and perhaps baby red dragons are the regular quest monster, replacing quasits. Enemy knights could also populate all of the levels except the goal.

Monk
The Monk has one of the worst and least flavorful quests in the game. All of its special levels are copies of other roles' special levels, most of the quest text is minimally edited from the Priest text, and the filler levels are standard room-and-corridor. Therefore, most of the quest, even its text, should be overhauled completely.
Starting at the quest flavor (noting that most of this is copied from the Priest quest): Master Kaen has assailed the Monastery of Chan-Sune with a horde of elementals. He killed the bearer of the Eyes of the Overworld and carried them back to the Monastery of the Earth-Lord, beneath which he lurks. It's not specified what he wants with them, except maybe generic world conquest. The Grand Master needs them back so that the monks can drive off the elementals.
The Monastery of Chan-Sune needs to be a different structure, or the Great Temple in the Priest quest needs to be. Perhaps neither should be kept; the level design is boring. The monastery's design should draw on the real-life Shaolin Monastery. This would mean some trees and statues in orderly rows approaching the main entrance, and perhaps a fountain here and there, with the same general pattern around the building. Perhaps there should also be a long wall crossing the level vertically before the approach to the temple proper. Inside, one would expect perhaps a longish hall with two rows of pillars with the Grand Master at the far end. (Incidentally, can his name be changed to Bodhidharma?) The pagoda forest from the real-life monastery could also be added, in the form of 1x1 and 2x2 areas of wall (there isn't really any better terrain) off to one side; bonus points if digging these causes an alignment penalty. Some other structures could also be added, but they should ideally be more interesting than an empty walled rectangle with one door. And as always, the downstairs should be opposite the Monastery, not inside it.
The filler levels need to be thrown out entirely; the Monk is no longer in a dungeon and should not be traversing one here. The upper filler is an overworld journey to the Monastery of the Earth-Lord, and should feel sufficiently Eastern and mountainous; of course, NetHack has problems with depicting height in any way, so that is not really possible. The level should be crossed from left to right, and should have the general aesthetic of normally peaceful wilderness; with things like scattered trees, small pools, natural springs (a fountain with a line of water going off the edge of the map?) and maybe some protrusions of rock from the edge of the map towards the center (might be accomplished by using a cavern fill that is more enthusiastic to carve out rock than the standard algorithm).
The Monastery of the Earth-Lord could go a few different ways. The original plan was to have it be a smallish structure at the right side of the map, where the hero would have to ascend a series of fairly wide switchbacks to access it (a level design very friendly to the xorns and earth elementals that populate it, and very unfriendly to the Monk); however, the lack of usable elevation would hamper this again. Switchbacks could still be implemented as walls, but then they would basically be flavored as actual walls built on the switchbacks. It could be a mostly underground structure built into surrounding rock, which works with the theme of being an earth temple, but the backup plan for the Tomb of the Toltec Kings is already very similar (not that that should stop it; it would just require the structures to be significantly different). In either case, the quest does turn downwards after this, so the downstairs should be inside the Monastery itself.
Lower filler levels are underground, and unlike many of the other special levels, they actually *are* the basement of a structure; however, they should not simply use the standard dungeon fill they have now. Rooms randomly and chaotically attached directly to each other, containing random pillars and walls, would be good here, and additionally, some lava pools could be added after everything else is generated, indiscriminately replacing the terrain (except the stairs). The random traps here are randomly chosen from fire traps, trap doors, falling rock traps, and land mines.
Master Kaen's level should not copy the Priest quest's, though the lava theme itself is fine. It should take longer to reach him than just standing on the stairs and making noise. Possibly some rooms on the left side of the level, the deepest structural part of the Monastery, could give way to lava plain on the right side. Or else the level could be built such that it is the deepest part of the Monastery, with Kaen sitting in some lava-filled rooms. There also does not really need to be an altar on this level.

Priest
The Great Temple suffers the same problems as the Monastery, since they are the same level, namely: it's a big rectangular box in a big field with a few scattered trees, and a lot of the space inside the box is useless. The first thing to do is open it up more, to two or even four directions (like the Temple of Nalzok, actually). The altar should be at the center, with side rooms minimized. Either the interior or exterior wall should be crenellated like Vlad's Tower is, except with niches 1 space deep instead of 2, with statues in these niches. If inside, the statues should be of priests, acolytes, and minion-type monsters; if outside, they should be random monsters or gargoyles. The surrounding terrain should be upgraded from its vaguely forest aesthetic to what a thriving Great Temple would normally look like - some outbuildings, well-ordered trees (maybe even fenced-in orchards, maybe even a small beehive with a few peaceful bees), a fountain or three, and perhaps a small graveyard (not filled with undead, just six or so neatly arranged headstones in a partitioned-off area). The downstairs are on the far right of the level, opposite the entry portal.
Upper filler levels are an overworld journey across unspecified land to the Temple of Nalzok, thus the room-and-corridor fill should be replaced. For this fill, a forlorn aesthetic would work well, making for a trek through dark and foggy open lands with scattered graveyards (the real kind populated with undead), some of which must be crossed in order to walk across the level. The upstairs will be placed along the left edge of the level, and the downstairs within a graveyard hugging the right edge. These graveyards should be around the same total size as the three graveyard rooms that exist in the current filler levels, and should be mostly fenced in. Happily, NetHack does have suitable terrain for doing this - iron bars, which are appropriate for graveyards. The whole level should be dark and have random scattered clouds and lines of petrified trees (adding a hedge terrain would be nice here too); this adds to the flavor of the quest. The dungeon apparently specifies that there should be only one upper filler level, but it does not have to stay that way.
The Temple of Nalzok is mostly fine, though one could make an argument that most of the empty space on the left of the level is underused, and the temple should be shifted left, with some trees and clouds scattered around the right side (or mirrored, since the hero would expect to be arriving from the left). The large graveyard is fine, but it should get a derelict fence surrounding it (accomplishable by manually specifying a fence with a couple gaps and then calling REPLACE_TERRAIN on it to destroy some of the bars at random and put normal floor there instead). Again, the entire level should be dark.
The fact that the quest again descends into the basement of a temple is annoying; perhaps this level should be a sort of outpost of Nalzok instead of The Temple of Nalzok. How about the hero arrives in the upper left, cut off from the rest of the level by a narrow (crossable) stream, with one other small graveyard somewhere on the far left, with the rest of the level being a mountain pass on the right side (marked by undiggable rock tapering in from the top and bottom of the map) guarded by the two priests of Moloch in an unaligned temple, the same as what exists now, but with no surrounding graveyard. (Locate level name: "The Demon Pass".) This would allow the upper filler algorithm to be reused for the lower filler levels, and then the more elaborate Temple of Nalzok would be the goal level, complete with large surrounding graveyard, one or two hostile priests of Moloch, and Nalzok himself on an altar in the center.
If Nalzok's Lair is instead to be kept as a generally lava-themed level, apart from other improvements similar to those given to Master Kaen, give it a special property: the level behaves as part of Gehennom, blocking prayer and other bonuses you would normally enjoy, and demons and similar denizens may appear here.

Ranger
The Ranger quest consists of forest traversal until the Cave of the Wumpus, then descent into the Cavern of Scorpius. This is not really well-flavored for either the Ranger or Scorpius to go into yet another cave, so the quest will be changed to be entirely horizontal. Instead of descending into the Cave of the Wumpus, the player must pass through it instead and come out the other side.
The Home level needs to die forever. I think the concept of moving from a lightly forested area into a heavily forested area and then a grove is fine, but the single-wide forest corridors everywhere must go. I think that Khor's proposed level works fine with only a couple of modifications (using REPLACE_TERRAIN to randomize the trees on the right side because why not, making the trees form less of an obvious border, and sticking the downstair on the left edge). Also, there should be a peaceful large dog named Sirius generated near Orion (the real deal, not the puppy you start with), and there should be a coaligned altar in the grove (the level is themed as a place of worship to your god, it seems very odd not to have an altar).
I have worked with jonadab on an algorithm to generate realistic Ranger filler levels, and it is currently pretty good. It does not generate strictly separate trees and floor like the current cavern fill; instead it generates a fairly dense but still navigable forest with some pools and rivers, and also a wideish guaranteed tree-free path between the stairs (which is not usually obvious that it is the correct path). Upstairs would naturally be placed at the right edge, and downstairs at the left. Some boulders should also probably be scattered here and there.
The Cave of the Wumpus is fine, but should more clearly be a journey through the cave and out the other side. Forest filler should be used on the left and right sides of the level, with the cave itself still being plain unwalled rock. (If maintaining the current flavor text for entering the level, perhaps there should be no filler on the entry side, with the cave being right up against the edge.) The current cave layout is not particularly good for a sideways traversal of the cave; perhaps the 20 rooms need to be rearranged, and there's no reason the map couldn't be expanded, either. It could even be a full-level map with only a small region of open area by the exit. Terrain between the rooms should probably be corridors instead of the floors it is now. The wumpus is not generated in any particular room; it might be in any, except for the starting room. As a special mechanic (and to make the wumpus actually threatening), it is able to instakill you with its normal melee attack on this level only.
The lower filler levels use the same forest filler as the upper ones, but the level is now dark with some scattered clouds here and there (fog).
Scorpius' Cavern is, of course, discarded. He's not constructing a subterranean complex like the quest text says. He doesn't need a throne. He's a scorpion. The design of this level will be informed partly by whatever better motivation we can find for him, but assume for now that he has just retreated here to the deepest, darkest part of the forest to plan his next move or something. Thus, this is a dark, even foggier forest level like the fillers, with no water (or else a lot of non-random water that you have to cross, like a wide river with stepping stones). That's not to say that there shouldn't be some signs of fortification: in particular, iron bars should be generated here and there between trees for centaurs to use as arrow-slits, and there should be rather more boulders generated here than in the rest of the forest. Scorpius himself sits in a small glade near the left edge of the level, with his entourage of scorpions and centaurs.
Quest text: the motivation for the quest is lacking a bit. It doesn't explain why retrieving the Longbow of Diana will help break the siege (especially since you immediately leave with it), and Scorpius' motivation to steal it is only that he likes it. Also, Scorpius being a scorpion, really shouldn't speak. His maledictions and other associated bits of text should be turned into angry hisses and whatever other sounds a giant scorpion would make.

Rogue
The flavoring of the Rogue quest is excellent. The leader feels unique. The motivation is realistic. The nemesis actually doesn't want to kill you. It is, overall, unlike any other quest.
This does not mean its levels are great, though. It uses a fairly bland locate level and a confusingly complex home level, and boring room-and-corridor filler. (The goal level is good, but has some problems too.)
First, the Thieves' Guild Hall (which the game should call Ransmannsby since the whole level is not the guild hall). As with the other special levels in this quest, the main danger is a chameleon transforming into an out-of-difficulty monster like an arch-lich and destroying the player, so their placement here is not great; the three special levels could stand to do with fewer of them, or none. The overall problem with the level design is that it is almost all alleys (hard to move and maneuver in, which seems odd for a Rogue not to be able to do) and there is a lot of dead space; most houses are not worth exploring unless you are trying to find all the items. Widening at least some of the paths to 2 spaces is a good start. Then, there is a clear attempt to design the level with lots of secret doors and clever passages; random generation could make exploring and finding the secret doors a key component of uncovering the level. Specifically, things like randomly blocking a street with walls but opening up a pathway that goes through a back door in a secret closet in the back room of a nearby house, and fake secret doors that look like they lead somewhere but actually just lead into a dead end wall (except occasionally they do, and the dead end wall is actually another secret door that leads in). Additionally, there should be at least one small shop here, such as a 2x2 general store. (I don't think it's possible to create a store with a shopkeeper but no goods, but if it were, that would be ideal - the thieves have already stolen everything from him!) If importing monsters from other games is allowed, the SLASH'EM and UnNetHack mugger (from a competing thieves' guild), perhaps buffed up a bit to Quest difficulty, would seem at home here.
It's not defined whether the Thieves' Guild and the Assassins' Guild are in separate towns, but assuming that they are means that the filler levels need not be town filler, which would interfere with the planned Tourist fill. In this case, upper filler levels can be a simple inter-town roadway. Stairs are at opposite ends of the level, as usual, and the game generates a somewhat winding path from one to the other, ensures no obstacles are placed within one or two squares' radius of this path, and the rest of the level on the parts not near the roadway, could be forest, water, walled rock, open space, whatever. (Grass and hedge terrain would be very nice fillers here as well.) Strategically, a level like this will probably be more difficult to play because it will be easier to get mobbed by the level's nymphs. If game mechanics made this possible, there could be a chance of generating a stopped coach or horseman (with peaceful horse) or something on or near the road, in case anyone wants to play highwayman.
The locate level is also completely replaced, because while its level is unique, it's not really that interesting or different from a cavern level. Instead of being already inside the Assassin's Guild Hall, i is the entrance to the other town it is located in, plus a portion of the town. It contains the end of the road, with a walled bridge (covered bridge?) crossing over a 4-wide or 5-wide river, with the town walls close by. The town gate is 2 spaces wide. The key mechanic of this level is that there are sessile watchmen posted in front of the gate, in such a way that you cannot walk through without being adjacent to one. They will challenge you when you try to enter, and will require you to obtain their permission to pass. If you walk into the gateway (the last acceptable space) without permission, they will say "Ahem! You are not authorized to enter this town." If they observe you entering without permission (if you move from a space in their line of sight to one inside the town), they will become angry and blow their whistles to anger all the other watchmen in the town.
There are a number of ways to pass into the town:

Anger them by walking in anyway or attacking them in some manner. ("Hey, you! Get back here!" if you walk past.)
Teleport in.
Dig in, but if a watchman sees you trying to dig the outer wall they will be angered.
Walk in while invisible.
#chat to them; they will say "Papers, please." and prompt you to select something from your inventory. You can give them any of:
a scroll of junk mail (maybe the horseman you can rob on the filler levels is carrying one),
200 or more zorkmids,
any valuable gem; however, worthless glass will anger them
anything else will simply not be accepted and will not anger them - they will say "I don't care about your 

<item>". Escaping the prompt is also fine.
The downstairs into the Assassin's Guild will be well-hidden, in a back room or secret area off one of the alleyways. Its location will be randomized among the several available places. There should also be a stable here with several horses; if you tame a horse in the sight of a watchman, they will be angered.
Lower filler levels are floors and subfloors of the guild hall itself, so while ordinary room-and-corridor fill could work, it does not feel quite right. For this purpose, I propose a different room-and-corridor generation algorithm: rooms that are either adjacent, or connected by a straight hallway (which is like a 1xn room lined with walls, using normal floor, and with doors on either end). The hostiles here should also be primarily "assassin" monsters; nymphs and leprechauns will probably still have to make an appearance but should be cut back from what they are now.
The goal level is mostly the same as the current goal level, with some tweaks. First, the level is made teleportable (it isn't currently), but the Master Assassin's entire area is now a unteleportable region similar to the Wizard's Tower: you cannot teleport into or out of it, though unlike the Wizard's Tower you may still fall into it from above. The benefit of doing this is that now the two regions that used to be completely inaccessible by normal means have teleport traps in them, which the player can use to eventually return to the region containing the upstairs, removing a massive source of frustration for players who fall to one of the inaccessible areas and lack the means to escape. Changes to the regions are as follows:

Region 1, the leftmost containing the stairs, is fairly unchanged, and is mostly bereft of objects. It no longer extends as close to the Master Assassin as it does now, so using noise to wake him up will require a higher experience level.
Region 2, the Master Assassin's area, is also fairly unchanged, down to the chameleon tin in a secret room. If we do change things to make it possible to fall into this region, perhaps there should be a cursed scroll of teleport here instead, and we can move the chameleon tin to Region 4 or something.
Region 3, the $-shaped pool with eels, is mainly useful for being the closest to the Master Assassin and the easiest from which to wake him up. There is nothing else of particular interest here, except a newly added teleport trap.
Region 4, the series of rooms that ultimately goes nowhere and is far away from the Master Assassin, serves as the Assassins' storerooms. The 13 random items that were previously scattered around the level are placed into storerooms here. There is also some sort of gold vault here, or possibly a leprechaun hall, and a newly added teleport trap.
The Master Assassin has a unique motivation here: he wants to keep the Master of Thieves from getting the Master Key of Thievery at all costs, not for any personal gain, but because the Master of Thieves would use the Key for evil. He does not particularly want to kill you, and is willing to be reasonable with you. Therefore, he is generated peaceful; if you wake him up he will warp to you only once, and will not do it again unless you anger him. If you #chat to him either before or after angering him, he will offer to give you the Bell of Opening if you will go away and let him keep the Key. If you accept he will let you have it, and be pacified (and you can still go back and kill him for the Key later if you want to). Moving next to the Master of Thieves when holding the Bell but not the Key will anger him

Samurai
Flavor for this quest consists of feuding daimyos Lord Sato and Ashikaga Takauji, with Ashikaga having recently assailed the Castle of the Taro Clan and stolen the Tsurugi of Muramasa. Lord Sato needs it back before the emperor arrives and forces him to commit seppuku for failing in his duty, so he sends you out alone after it. The motivation here could use some work, but the real question is why he doesn't send more than one person, when one alone could easily die. The friendlies don't seem to be needed to defend against the roving ninja, as is the flavor in other quests. It might make for an interesting mechanic if half of the roshi on the level were automatically tamed and could accompany you on the quest.
The Castle of the Taro Clan is very boring. It appears to be intended to be on some sort of hill overlooking a town, from the entry text. It has little in the way of fortifications and basically nothing interesting inside. (This should NOT be a loot-heavy level, since the rest of the quest is quite rich with it, but that is no excuse for the castle being basically six empty rooms attached to Lord Sato's chamber.) The castle should be shrunk down and maybe given some mildly interesting surrounding features, like trees. It should probably not have a moat. Inside the castle, there could be a number of interesting rooms: a kitchen with a sink, a lawful altar, a fountain, a library (with two or three spellbooks in it), an empty barracks (not a special room) with beds and things like that. But none of these rooms really need to be as big as they are currently, so the castle can safely be made smaller. To the left of the castle, a wall stretches from the top to the bottom of the level; beyond this wall is forest (and possibly one ninja). There could be a doorway in the wall, or not. On the right side of the level, the stream is moved left somewhat, and the downstairs are placed in the top right corner. I'm not sure if some empty small buildings should go in this sector to show that this is the town.
The upper filler level is crossing whichever terrain happens to lie between the Taro Clan's town and Ashikaga's fortress. This could really be anything, and it's vague enough that I feel like reusing one of the fillers from the other quests, like the Rogue road filler, would be fine. There should be one or two ninja added to this level.
The Shogun's Castle (according to his encyclopedia entry, Ashikaga is a shogun as well as a daimyo, in which case he probably has the authority to take and keep the Tsurugi lawfully and is not particularly beholden to the emperor, but I digress) is pretty good already. I don't quite like the design of the corner towers, as they seem to be dead space; adding iron bars seems like it would help make them more useful, especially if the ninja were moved into the outer chambers of the castle where they could toss shuriken at you. Then, the castle should have a moat and at least one drawbridge; it is supposed to be hard to gain access to it, and walking around one corner and opening a door doesn't cut it. Perhaps the entire castle should be stretched vertically by 1 space so that it is an odd number of spaces high, which would permit a drawbridge to be added and keep the symmetry, probably on the right side of the castle opposite where the player enters. Then, the exterior just needs some more detail than the plain field it currently is; trees are fine but something more imposing would be even better. Possibly the whole right side of the level is a large lake that connects to the moat. Somewhere in this castle should be a stash of ya that the player can restock with, or some of the enemy samurai here will carry some.
The lower filler levels are excellent as is, except the secret doors should really just be regular doors, and the upper levels ought to match or be smaller than the footprint of the castle in the locate level. Ideally, the rest of the quest would be ascending the castle, not descending it, and the stairs in the Shogun's Castle would be going up, not down, but there are technical reasons why that can't be done (it'd need a whole overhaul of the dungeon code). The stairs should also generate a certain distance away from each other - the level's pointless if they are right near each other.
The goal level is okay, and doesn't really have any flavor other than the topmost/bottommost floor of the castle where Ashikaga waits. Perhaps some cloud terrain could be scattered around this level with low probability. The edge should be ringed with walls, not rock. Apart from that, I cannot think of much else to change.

Tourist
A number of nitpicks with the quest flavor text:

Ankh-Morpork has no elected mayor. The Master of Thieves doesn't need to gain it through elected office - merely stealing the card is sufficient.
The theft of the Card does not threaten the city itself, only the tourists. Messages like "Things appear to have become so bad that you fear that soon Ankh-Morpork will not be here to return to" should be changed.
The Master of Thieves is the same person as the Rogue quest leader but is remarkably more well-spoken; his lines should be more uncouth than they are now.
The Master of Thieves is not a magical being and his "earthly body" should not "begin to fade before your eyes". He should just die.
Giant spiders as the main quest monsters don't make much sense; these should be changed to leprechauns, nymphs, monkeys, and other thieving monsters, or human thieves/muggers - tourists are known for getting pickpocketed. Leprechauns generated in this quest should carry no gold (though watchmen should).
The home level should look more like the outskirts of a vast city, not a single largish guarded building across a river. Most of the space on the bottom and the left is pointless, so this area should be shrunk to allow for a more interesting city design. This will include a wall across the upper portion of the level, encompassing the top right corner and maybe the top left and bottom right corners as well. The hero will arrive in the lower left corner, outside a gate guarded by two sessile watchmen (these do not try to bar your entry like in the Rogue quest). Since this is Ankh-Morpork, the river should "flow" through the city and out its walls (muddy swamp or sludge terrain would be even better than water, though, since the river Ankh is definitely mostly not water), with a bridge across it inside the walls. The friendlies and Twoflower should occupy one smallish building near the gates, and the stairs should be somewhere inside the walls along the top right edge, perhaps at the end of the main road. All roads should be more than 1 tile wide because of the fairly high number of peacefuls, and some of them (like the main road inside the gate) should go at an interesting angle instead of having everything be orthogonal. The graveyard outside the city is placed somewhere else outside it, probably still across the river, or else it should be moved into the city. The no-teleport restriction is lifted.
Some of the rooms from the current locate level are moved into the home level, including at least one of its shops, possibly one of the barracks and maybe the zoo. Monsters on this level include one or two roaming watchmen and several peaceful dwarfs, trolls, and humans, some of which are generated inside empty houses.
Upper filler levels should be town-themed; this quest occurs entirely within the city. I believe L wrote a generator for town-style filler levels, and this can be either used or adapted for these filler levels. Again, most roads should be 2 tiles wide and 1-tile walkways should be reserved for short alleys only. The player proceeds from the lower left to the upper right. No particular special rooms should be added here, because if they are randomly generated it makes it harder to balance the quest loot.
The locate level is now The Shades, and the goal level is now the Thieves' Guild Hall. This is because one would expect to find the Master of Thieves in the Thieves' Guild Hall, whereas the Shades are a dangerous region of the city one would expect to have to pass through to reach the guild hall.
The level is now traversed left to right. The police station is moved to the lower left side of the level, and its Kops are removed; it is populated with 2-3 peaceful watchmen and a watch captain instead. Special rooms on this level are the treasure zoo, two graveyards (one of which is stolen from the goal level) with some trees, two shops, the secret throne room, and the abandoned temple. When redesigning this level, lots of twisty back alleys and secret back rooms, none of which are actually needed to traverse the level, should be added. Various interesting things can be placed in such spots, like a sink or two, a disused altar, an out-of-depth or unexpected enemy like a vampire lord or a werewolf, a foocubus, a group of hostile trolls, etc. There are three foocubi in the back room of one of the houses. Several houses here have iron bars for windows. This is a prime place to use iron doors, if they can be added. Also, if any more Discworld references are desired, this is a prime place to add them.
Lower filler levels are the same town filler as the upper ones, traversed left-to-right as before.
The Thieves' Guild Hall should consist of a small portion of the level cut off by the river in the upper left corner, in which the hero arrives, with two bridges crossing it to the right and bottom. Buildings persist on both sides and across the level, with their complement of mostly peaceful dwarves, trolls, and humans, and the Thieves' Guild Hall, while about three or four times larger than the surrounding buildings, is not particularly unique or imposing; it does not even stand by itself, as other unrelated buildings are attached to it. A stable similar to the Rogue quest would not be out of place here. There should be some subtle hints to the wandering player, such as a double door, that this building is the destination. There are no "friendly" special rooms here; there are three barracks in the surrounding buildings, with no doors in the doorways, and there is a leprechaun hall in the Thieves' Guild. The Guild itself contains a simple arrangement of rooms, including an antechamber, a large common area, a secret door to the Master of Thieves' chamber, and a secret door in the back of the Master of Thieves' chamber leading to the vault, which contains the leprechaun hall, two chests with random contents, and also a room of gems. In the common area will be a few nymphs and maybe a rogue player monster or two. It would be ideal if a new trap type could be added here that would set off a loud alarm noise; this would be placed just inside the door to the guild such that it would wake up the Master of Thieves, the leprechauns, any nearby nymphs, and the nearby barracks if the player has not already cleared them out.

Valkyrie
The ice theme on the home level is great, as are the interruptions of fiery lava and water (having lava and water next to each other is a little odd but the scale of this level won't really allow for more detail). However, the Shrine of Destiny needs work - it should be more than a boring rectangle. There are various building designs possible, but what needs to be clarified is what the usual purpose of the Shrine of Destiny. The Warriors that currently occupy it are temp workers from Valhalla, and not normal attendants. Does the Norn usually just sit here by herself with the Orb of Fate, or are there any other people around? If she is alone here, the shrine should be probably a bit smaller than it is. If there are some other regulars, there might be a few stark living areas. Perhaps there can also be a small round room with an indoor tree, or something. It would be nice if the chest (or a chest, more could be added) also contained a guaranteed spellbook of cone of cold.
Another possibility for this level is to put the Shrine in a mountain pass (it's already on a hill as per the text), with it in a small clear space in the central part of the map and large protrusions of rock coming out of the top and bottom of the map, with the downstairs somewhere on the right edge. Some monsters will be on the portal side, but more on the stairs side. Maybe you have to pass through the building to cross the level, but maybe not.In either case, the portal should be on the left side of the map and the downstairs on the right.
Upper filler levels are fine if not rather bland. It'd be cool if it could be a "snowstorm" level, but it would take some pretty large changes to make a realistic snowstorm, and Surtur and his entourage have recently come through here - perhaps their fire powers vaporized any snowstorm taking place. I see no reason for this to be a big open field with *no* obstructions of any sort. Certainly there should still be some scattered lava vents, and maybe a cold unfrozen pond. Maybe also some "islands" of walled rock, so while the level is still an ice field, it is broken up somewhat. There could be a tree here and there, too (though it bearing tropical fruit when kicked is wrong...) Stairs are on opposite edges of the map, as always, perhaps with the upstair on the top and the downstair on the bottom, placed pretty far apart horizontally.
The locate level and the rest of the Quest should be themed as Muspelheim, the Norse world of fire and Surtur's home, instead of the boring "cave of Surtur" (and the finally-assigned-the-quest text should be updated accordingly, maybe noting how you need to journey "far to the south"). The locate level, then, is the gateway to Muspelheim. Assuming the entryway is small, this will probably still have a "cave entrance" feel, in spite of any other details that can be provided. Perhaps it can be a large straight wall, with giants manning the parapets. (Alas, they cannot throw boulders down at you from the parapets, since there is no terrain that allows this.)
Another possible route for this level is for it to be based after the Bifröst bridge, the rainbow, connecting Midgard and Asgard (though here it leads towards Muspelheim). In Norse legends, the bridge will be broken when the Muspelheim forces ride over it during Ragnarok (which is now starting according to the Norn), so the bridge would be broken in this level after Surtur and the other giants have passed over it with the Orb of Fate. Then, this level consists of a wide irregular void (not sure whether it should act like a hole dropping you to the next level, or an eternal fall and instadeath, or something else) spanning the whole level from top to bottom, with the ice terrain on the left and the fiery Muspellheim terrain and a horde of fire giants on the right. Crossing the void is the straight bridge, which is missing a large chunk from the middle and may have a few floating fragments remaining (maybe enough to cross by jumping with jumping boots, or maybe it's randomly replaced terrain). You can fly or levitate (or possibly jump) across the bridge. The first time you enter this level having killed Lord Surtur, or if you kill him while on the level, the bridge is fully restored.
Lower filler levels are in Muspelheim proper, and should be appropriately fiery. I want them to be more than boring lava-cavern fill, but at the same time, there's not really any other terrain that could be used here, is there? The lava should not be quite so pervasive as it is now. The player should certainly not have to walk across one-square-wide isthmuses of solid floor like they may have to in the current level. One easy way to generate the level would be to use cavern fill and grow the area of solid floor by 1 in all directions, but this may still be too lava-heavy. Fire terrain (something I want to have anyway) would be very helpful here, since it would be less lethal than the lava. Scattered boulders (ammo for the giants!) would be good here too. Stairs are on the left and right edges of the map as usual.
The goal level should be continuing this general Muspelheim aesthetic, but of course it contains Surtur's house/fortress. I don't think it should be as challenging to enter as it is now; the difficulty of crossing the bridge and maneuvering on levels containing lava should suffice for obstacles. Thus, there should not be any drawbridges. Surtur's fortress itself is an imposing squarish (but not perfectly rectangular!) structure on the right side of the map, where Surtur himself waits on a throne surrounded by several fire giants. The rest of the level is the same lava-and-boulders as the lower filler levels, probably using the same algorithm. The killing-him message should be changed (he literally just "screams in agony, then dies" for no apparent reason, after the "You kill Lord Surtur!" message).
Quest monsters should probably be more fire giants than fire ants. The ants are kind of secondary to the giants, who Surtur is the actual leader of.

Wizard
This is a tricky quest to redesign because it is pretty vague. The quest proceeds from the Lonely Tower to the Tower of Darkness, then into a medium-sized lair or dungeon with some prisoners. The quest lacks identity mainly because it uses standard dungeon fill.
The Lonely Tower has an okay overall design, but it is a bit boring inside, with no real interesting part except the throne. The narrow twisty corridor that is usually blocked by several apprentices should be abolished. An interesting take on this is that the magic portal, being created by Neferet, could be in one of the empty rooms of the tower (quest entrance text would need to be changed, maybe you see the monsters out a window or something), so you don't actually have to find the entrance (which is kind of annoying to do as-is). I think the overall round shape of the tower does a decent job. Outside the tower, there should be the usual assortment of monsters. The tower and perhaps a region around it should be lit; the rest of the level should be dark. The fog hanging around should be randomized, and the stairs exit to the right. There should be a few trees scattered around, too. I have no opinion on the pond, it seems rather pointless but then again it serves to add a feature to an otherwise mostly featureless level.
Upper filler levels proceed left to right through a dark valley, with a narrow 1-wide stream of water running across from left to right without much meandering. The entire map is dark and uses a simple fill algorithm that makes the top and bottom edges rough solid rock. Perhaps there should be some ruined houses here, small rectangular or round structures with their walls randomly replaced with normal ground, and a few scattered trees near the rock walls. There are more wisps of cloud here and maybe some larger contiguous areas. (Maybe add some fog cloud monsters too, why not?)
The existing Tower of Darkness is fairly boring; the greatest danger here is falling in the moat by accident. To fix it, it should first be made less square; a sorcerer's tower seems like it should be round (as the Lonely Tower is, come to think of it). Then, the stream and valley the player has been following should taper out here; the tower is nestled in the upper reaches of the valley, and the rock sides close in on it but then open up into a circular area in which the tower is built. (Slightly inspired by the geography of Isengard.) There is no moat anymore, since the tower is at the top of a valley. Clouds and darkness persist here. There is one secret door randomized around certain points on the perimeter of the tower (you will have to use secret door detection or else search a lot to find it; unlike the Lonely Tower, you have never been here before). The interior of the tower is redesigned to be an actual functional building; nobody builds their house in a series of narrow concentric rings. Have some rooms with a sink, and the staircase in a reasonable place. The dungeon prisoners are moved here so that if the tower can somehow be made to go upwards instead of down, they won't inexplicably be on the top level. Possibly, there should be a powerful minion of the Dark One situated here preventing further approach.
Like the Samurai quest, this quest really ought to turn upwards here and ascend the tower to have an epic duel with the Dark One at the top, but unfortunately that is not possible with the way the dungeon currently works. In any case, lower filler levels are intermediate floors of the Tower of Darkness, so they maintain the same footprint as the tower base in the locate level, and have a series of directly connected rooms (making a filler algorithm for this would be nice), populated with the usual items and monsters.
The goal level should be fairly simple, with the same tower footprint. This level of the tower is more open, with perhaps only a short narrow corridor (representing a long staircase) connecting the stairs and the door to the main room, in which the Dark One sits. Or possibly a two-wide ring around the central chamber, with the door location randomized. He should not be on a chaotic altar anymore. Other monsters should not be too populous, either (though as an aside, it'd be sort of neat if the Dark One cast a unique "summon ravens" spell to blind you). At the opposite side of the chamber from the door you enter by are several spellbooks (may or may not want to put these in chests), which serve as the primary loot for this quest because it's lacking a bit otherwise.
Quest monsters should be a little more biased towards spellcasting monsters than they currently are; bats and xorns are not that compelling of an enemy for wizards. Barrow wights are a pretty good choice here, but so are liches and golden nagas.

Other notes
In general, the number of upper and lower filler levels per quest should not be random. It makes it harder to balance the quest loot.
For overworld type levels, holes and trap doors should not generate. This can probably be accomplished by making them undiggable-floor, which makes sense.
Several of the "when throwing the quest artifact to the quest leader" messages are the same, and probably should be changed up.
All non-randomly-placed containers on home levels should be untrapped.
Nice and necessary changes
Things that would be nice or necessary to add to make these things work, in rough order of how easy they are to add in:

Nice: Non-humanoid nemeses don't talk
Nice: Grass and sand terrain
Nice: Mud terrain
Nice: Hedge terrain
Nice: Wumpus instakill in the Cave of the Wumpus
Nice: Import mugger from one of the variants that has them
Nice: Iron doors
Nice: Loud alarm trap, also "summon mummies when picking up an item" trap
Nice: Some other terrain to indicate disease or sickness in the Healer quest (sludge could work and would also serve well in the Tourist quest)
Nice: Common monster in Healer quest with disease attack, would probably require a slight nerf to disease
Necessary: Bias stair generation so that randomly placed stairs are likely to be far away from each other
Nice: Fire terrain
Nice: Create general store with shopkeeper but no inventory
Necessary: Void or whatever lies in the gaps in the bridge in the Valkyrie quest
Nice: Parapet wall or similar to allow defenders to fire at you but you can't fire back at them
Nice: Split up teleport regions and no-fall-in regions to be independent.
Necessary: Road filler level algorithm
Nice: Generate horseman or stopped coach on road filler level
Nice: Watchmen get angry when you tame or saddle a horse in a stable that is not yours
Necessary: Tomb and town filler level algorithms
Nice: Unique spells for the Dark One and other spellcasting nemeses.
Nice: Roshi (or other friendlies) join you on your quest
Nice: Knight discovers the stairs in the locate level only after climbing the Isle of Glass
Necessary: Bridge in Valkyrie quest is restored once Surtur is dead
Necessary: Master Assassin is peaceful unless attacked and will give the Bell of Opening if you leave him in peace
Nice: Monks get alignment penalties for digging certain squares on certain levels
Necessary: Rogue locate level system of preventing access to the town until you "prove" yourself
Nice: Valkyrie filler is an active snowstorm, obscuring vision
Nice: Quests can go upwards after the locate level
Nice: Height values so that pyramids and mountainous regions can work better

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