Something that would be awesome would be a zombie mode where you and your team must try to survive so many waves of zombies, and if/when you die, you become a zombie too, and have to try to kill your teammates!
This game is fairly fun, but I think it could use a couple stationary, shooting, undamageable/killable towers along the side of the road so this game could be concidered a real TOWER DEFENSE game.
I must say, this is a very good game. The graphics are fairly good for this type of game, the design is superb, and the game is fun, challenging (but not overly so) and engaging. About the only thing I can think of that would improve it would be to make it so you don't HAVE to use all skill/caracture points when you are equipping them.
Something that would be awesome is if you could have some modes that allow people to use all but one type of weapon, like no sniper, or no grenades...... That would be quite nice.