well i have few ideas , 1 is an new zombie class like in half life the tiny dog looking thing that does the aoe stomp , 2 New weapon an machine gun with grenade launcher in it (max 6 grenades , does same ammount of dmg as an smg weapon Grenades are not rechargable) 3 New weapon , an melee sword received at 50 kills , does twice the dmg of an crowbar 4 New zombie thingy , normal zombies " yell " *mouse2" does an tiny screen shake(like wraiths) 5 With enough coins you can decide what pistol you spawn with ( from all pistols magnums etc) 6 With enough coins you can decide what smg / assault rifle you get at the ammount of kills needed (not random anymore) 7 Improved rtd , gives 3 kills 35 health reduces the fire burn . but the explode thingys % is increased 8 Temporal " spawn " immortality (lasts for 5 seconds when you spawn prevents spawn killing for humans) 9 Glory of last human , the last human does more dmg + gets an 30 hp when he becomes the last human. 10 Glory of first zombie , increased health + speed as far as i know any of these wont interupt the gaming at all, it would actualy make it even more fun well this is some ill ad some more when i get my idea sprees while sleeping ^__^