So I want make a Swedish meatball style meatloaf. When I make Swedish meatballs I usually use veal and ground pork, but I've always wanted to throw in some ground lamb and buffalo.  So the specific question here is for a meatball how many of these meats can I get away with including in these balls Of juicy meat?  And more generally, what are the guiding principles in combing meats from Different animals like this? Hoping there's like a periodic table of savory sensations I can put on the kitchen wall, but any anecdotal suggestions will be sufficient. 
They're meat spots, and safe (though unpleasant) to eat. 