Instead of buffing zombies to have super vision, hearing, and leather skin I say revert the zombies back to update 1.11 and add new artificial intelligence that I recommend below:
- AI human bandits that are looking to rob other survivors and eat their flesh in order to survive
- Vampires that come out during the night time to feed on zombies, pigs, sheep, real human players
- Werewolves that come out at night to feed on zombies, pigs, sheep, real human players
These new AI can spawn and appear just like the wolves do when they make their howling noises to give you a warning that they are near, and then they appear and attack out of no where. Or you can make some of these AI spawn in certain parts of the map to guard higher tier weapons and items.