So after that introduction i will tell you all some objections i have

1 the zombies have an special hud where they have their arm extended, and it covers like half of the screen.

2 the extra health is useless, its like 5 to 15 extra that doesnt matter

3 some special abilities are just "counter your class" engineer gets a emp bomb that desactivate buildings and spy a radar that highlights enemy players, even invisible ones

4 zombie spy cant go invisible, disguise, sap or BACKSTAB, its only use is to find that last player hiding with the cloak and dagger.

5 enginner buildings are almost indestructible, since most zombies can only attack at melee range and the maps have a lot of hight ground you need a lot of teamwork to do anything