In my own opinion, melee is certainly too good, particularly unarmed combat with its plenty of stunlocking techniques. As far as equipment, the thing that solves 90% of your problems is either an appropriate martial art trait, or an appropriate martial art book. The rest is just some basic protective armor against regular zombies, so you can grind the combat skills quicker, and that’s about it. Even at about 4 or 5 in melee, unarmed and dodging, you get to be a nigh unstoppable killing machine.
However, as a melee zombie-slayer and enthusiast, seeing melee just flat out nerfed in its current state I would very much consider a proper anti-fun move. As powerful as it is, melee is just one of two convenient ways of dealing with zombies right now. You either hit 'em to death, or you shoot 'em to death. And if I’m forced to just shoot 'em to death just for the sake of it, that’s basically just more keypresses.
What I would much rather have is proper support for variety in dealing with threats. Melee should be viable for most regular zombies, rather dangerous against Brutes or Soldiers, very dangerous against shockers or acidics, and straight out suicidal against Hulks. But there should be tools other than fight or flight - stealth, for scoping out locations before engaging in potential combat, proper tools for luring zombies out, such as perhaps intentionally triggered car alarms, things such as filthy clothing masking scent and reducing detection radius, etc. Zombies could also be made more scarce but more dangerous individually and more varied in things like speed, detection radius and similar, requiring more forethought in how to approach a situation.
Melee could then be made ‘realistic’, perhaps implementing limitations such as - you don’t want to hit a skeletal juggernaut with a katana since it’ll likely break, and the same goes for wanting to strike it with your first. Hulks being slower, but obliterating you if they smack you once, and so on.
Basically, what I’m trying to say is - nerfing melee to be ‘realistic’ would work best if melee is just another tool in a toolbox - being that the toolbox is rather tiny right now, nerfing melee is just meh.