I like the commitment to being a doom-like and removing head shots.
The basic shooting enemy is completely broken and does no damage, so sadly I can't judge much about the gameplay in the end.
The city level is sprawling way too much. At least add a map if you are doing that. I gave up after searching for the green door for god know how long. It also lacks visual clarity with all the darkness and countless small point lights. The hospital is a step in a good direction though, as it's recognizable from a distance. Some collisions are broken i.e. with stairs (one can be clipped through into the side, another makes you stuck). Level design has a lot of good shit going on though, so I believe you have the most important stuff figured out.
I think being able to shoot the pistol by holding left click is a mistake, although I'd have to retest it with fixed enemies.
How the hell does it run so slow? My gpu might not be an rtx, but below 50 in the tutorial is a bit... Thankfully the visual style still works with lower resolution.