I'm at the other end of this... Playing seems fairly balanced, but going from newb zombie to 3rd mutate holds zero increase in:
1. Hitpoints - I still take 3 hits or less
2. No increase to speed - if someone is good with dodge and dropkick, they can own me every single time
3. 4k damage weapons equate to a one-shot kill on me
4. Did I mention there's no way to deal with dodge+dropkick?
5. The human being able to vault every single tackle attack is crazy, I mean literally zero downtime to vault means they can counter tackle every single time (I've seen 1 guy do this, it was stupid)
There's probably other things I'm missing, but I thought zombie was overpowered until I started facing people who knew all the moves and had 4k damage weapons.
Then I came across the people using speed hacks.
The player zombie is easier to kill than trash mob zombies.