I personally would like to see more zombie games. But I want to see more unique zombie games, not just the usual mindless "RARGH ZOMBIES RUN AROUND AND KILL EVERYTHING!!1 MOAR DESTRUCTION!1!!" That just gets old.
That's why I like games like Dead Zone and Rebuild, because they added something interesting to the online flash zombie genre and they force you to think rather than just shoot. I didn't like Union City because it didn't really stand out too much from other zombie games; I only played it to see if there was background story to Dead Zone. I'm not as huge of a fan of Infectonator, because as amusing as it is, I find it mostly depends on luck.
I would also like to see more point-and-click adventure games on AG, like Reemus and Reincarnation. I find that most of the games under Adventure fit more under RPG or Arcade or Puzzle, and a good point-and-click seems to be harder to find here.