I've been playing Zombie Mod servers since they came out with the mod. The only issue I have with unlimited ammo is, when you get 10-15 people on 1 spot, it gets a little ridiculous. Maybe have zombies spawn with more health each time they die. Or have some sort of a ratio system where if there is 7 zombies to 40 people, have them spawn with a lot of HP to counter the amount of human players. Or put a limited number of people per spot on a map. Just an idea, I know this would cause issues in the server and cause more problems but I'm just throwing my idea out there.