I have played it a fair bit over the weekend and here are some of my thoughts about it.
Yes, the night time stuff with having to snort shrooms or take inhalers is a real downer. Although it does make exploring at night a real pain it does add tension. It also scales as you level up your health and stamina. I think i am at about 7-8 mins on a full UV Charge. You also get UV Flares/lights that you can pop in a safe area and recharge fully.
The graphics are OK but not great. Pretty much looks like the PS4 Pro but a little cleaner. The draw distances tho are great but i have also found the frame rate, even on performance, can dip below 60 at times.
It has quite a few bad bugs, these range from getting stuck in places that you cant get out of and have to either kill yourself or quit to continue along with graphics/model/texture glitching and clipping problems.
There is a lot going on in the game and at times can be a bit overwhelming, maybe its because its a little more in depth like RPG than i am used to. I have done a decent amount of the campaign and not really even touched any of the night zones or super infected areas like the GRE facilities.
The weapons and clothing/armor system is very complicated. Its really tough to see the difference between different items as the stats are shown in percent and there isnt a compare to what you currently have equipped.
Also i got into a weird bug that was a real pain to get sorted. After i got to the second part of the map fast travel opens up and you get the paraglider, I had played through the new part of the map, done a couple of missions and thought i would go back to the first part of the map and do some of the missions back there before continuing. Only problem with that was that for some reason there isnt automatically a fast travel point in the new part of the map and its bloody hard to get back there and takes quite a while and there is nothing telling you how to get there. I had to google it and watch a youtube video. After all the delays it doesnt look like there has been a great deal of QA on this product.
One tip i can give is to get your health and stats up so you can get the Drop Kick ability.. Its great fun and sends the zombies flying
The ai on the human enemies are a bit more clever and can dodge but its sooo satisfying drop kicking a zombie off the top of a building..