At this point I think I've played 8 hours at least, I've beaten the game, and seen what I assume must be every area. I'm really impressed by the game and it's clear how much work has gone into it. It has a great sense of humor, a wonderful aesthetic, and I love some of the more subdued and quieter areas in the game like the Museum, Ghost Buffet, Necropolis, Paradise Garden, Cosmos, Lonely Apartment, etc... in comparison to the many loud, abrasive areas just absolutely chock full of stuff. I'm really glad you decided to release it and I hope that releasing it will mean you can take a break for a while and let your mind cool down after spending so much of your life working on this thing. I know just as well that a project like this can sort of destroy your brain over time.
As far as negatives, I wish the 3d-space-swirl/spin effect when you get hit by bombs or touch meat/conveyer belts, and the fact that hotdogs force you to vomit for 10 seconds (which makes the game near-unplayable in many areas when you unblock the hotdog factory) were changed. Perhaps an Iron Stomach upgrade to make it so you can eat hotdogs like burgers instead of getting force-bezoar'd and an Iron Equillibrium upgrade to remove the spin effect would do a lot to help the quality of life.
The lighting is obviously not ideal but you're clearly aware of that, so I don't think it helps to mention that, and I love the aesthetic of the whole thing, I just wish some areas weren't so mind-meltingly bright in the bedazzled version.
The character controller seems to have a glitch that causes it to frequently veer off in one direction rather than go straight forward much of the time, I'm not sure what causes that but it can be pretty annoying sometimes.