After running around in this for a bit, I can say this is definitely up there with one of the more realistic backrooms games. The level generation is fantastic and the lighting is just, wow. Some feedback I would give is there needs to be a way to decrease or disable that camera shake effect. It gets pretty hard to play with after awhile. I'd like to see some more variation in wall height (such as walls not going all the way to the ceiling), flickering lights, completely dark areas, and a much more noticeable fluorescent "buzz" sound.
I don't think adding a "survival system" or any "monsters" are necessary, as it's enough just focusing on making the actual levels as creepy and unsettling as you can. If you do plan on adding any later though, I'd recommend having an option to toggle them on/off or having a "free roam" mode.
Other than that, great work. Keep it up!