I was thinking of something starting out more along the lines of resident evil 2 (the game), dawn of the dead (remake), or zombieland. The only problem is that people would be really upset if their characters die, so it would probably be best to have only one or two actually players (Possibly controlling more than one character, depending on the type of story). I love the stories in those old playstation games like resident evil 2 and parasite eve. Would probably go with something similar.