Overall, the game is a mess. Combat is just something you dread, not because of any horror angle - but because it's long, boring, and uneventful. The worst thing you can do is make a lot of noise and get swarmed, but the game provides a lot of ways to avoid making noise. The hardest encounters are against human groups, but you can often bait them into wasting ammo and making a lot of noise and suicide themselves on the nearby hordes.
The NPCs are non-reactive for the most part. You get an introduction to each one you recruit and then there are sometimes a few events... But it's pretty shallow. It's fun to try and "collect them all", however.
Supplies are not hard to manage. It's very difficult for your survivors to be inefected with the zombie virus, despite taking hits to the face frequently. Chance is so low none of mine got infected on my first playthrough.
The lack of AI for human and zombie opponents sucks dick. You can exploit things like closing doors to make enemies forget you exist. Zombies and humans generally stand around without any agency and only react to noise or sights near by.
Only a few areas of the game are "tactical", most of the time it's straight forward baiting with ranged weapons and carefully whacking zombies to death. There are some horrific zones, basically anything with multiple floors the game engine can't handle very well.
The game is aesthetically ugly, which wouldn't normally matter, though it does make the aformentioend multi-level areas kind of bad.
In general, the game is mediocre. If you like exploring and hoarding stuff, the game will hold you for just one playthrough. The story isn't gripping and the reactivity just isn't there. The game world is also very static, at least in its layout. Random events make the game a little better. The fact zombies slowly remove resources/NPCs from the game world adds a little pressure to the game, too. But overall, it's just a failure of a zombie RPG.
I want to try the overhaul, but I couldn't make myself play the game again. It just isn't worth the investment, there's no payoff. Character advancement is dull and there's not a lot different to do. You can already get very effecient at the game in your first playthrough to be satisfied with its ending.
Better luck next time, I guess.