How Long Should A First-Person Shooter Story Be?

In today's Speak-Up on Kotaku, commenter Crushinator ponders the correct length for the single-player story in the increasingly multiplayer-focused first-person shooter genre.

Many of the reviews of Homefront lately have lamented its short single player campaign, and that was enough to make me not want to buy it. I usually enjoy single-player games much more than multiplayer (not counting co-op), and I don't usually want to shell out for a game without a good story-driven experience.

But something Kaos GM David Votypka said struck me as odd. He said they'd consider making the sequel longer if that's what fans wanted. I understand that they needed to balance their resources and wanted to focus on multiplayer, but it got me thinking, if Kaos thought they didn't need to make Homefront all that long, do most FPS fans really want a longer single-player game?

I know not everyone wants to play through a 30-hour epic like Mass Effect or an Elder Scrolls game that could quite possibly never be finished. Some people want a game they can polish off quickly. But even if it has "replay value," paying $60 for five hours of a campaign feels like a rip-off to me. I'm happy with the few multiplayer games I have and don't feel the need to buy yet another Battlefield or Call of Duty clone just for multiplayer.

I've always felt games like Bioshock or Half-Life 2 hit that 15-20 hour sweet spot. Titles like these have such excellent gameplay and pacing that they can sustain a longer campaign without getting stale. When the credits roll they leave the player with the impression that they've just completed a fulfilling journey rather than a quick diversion before the multiplayer.

Am I wrong? Are there people out there who appreciate a longer shooter? Or are most people happy with a six-hour game?
