great job (both of you), in that case!
just cleared the game again. still fun! I appear to have improved in my sleep, as well.
it depends on the tone you are trying to set [with lighting]. on the one hand, it feels dark in an unintentional way. on the other hand, I now associate the feel of the game with how dark it is (and I like it). there are some parts of the map where this leads to readability issues that are probably too egregious to ignore (stuff you just can't see) but all in all it's a personal design choice. there are no wrong decisions.
realism, physically-based rendering, etc. would seem to clash somewhat with the 'shareware' direction you have cooking. baking vertex lighting into your meshes and leaning into photogrammetry seems like the natural next step--this is why I brought up the revolver: it's one of the few untextured and unprocessed assets in the game (or it at least appears to be), which makes it stand out.
I understand wanting to avoid guns in general--it's something that many of us are feeling these days. at some level it is difficult to overcome the fact that your game somewhat centrally features a firearm in the workplace (i.e. this might be one of those 'lean all the way in' or 'run away screaming' thematic/tone decisions). however, one of the things you can do--if 'comic looking' is indeed your goal--is mess with proportions. the current asset is essentially a scale revolver.
probably the most significant observation I have re: the lighting is that it appears largely to be direct (and quite harsh). you have many light sources, but not much indirect lighting (i.e. not much bouncing, and therefore not much diffuse light). this leads to patches of absolute dark surrounded by patches of brightness. you can resolve this with some kind of GI solution, baking/lightmapping, or just by adjusting your ambient. the latter is the fastest trick in the west and will probably get you more bang for your buck, but given your visual style, baking would seem to vibe more. all this stuff is up to you--how do you feel about the lighting? given that this looks like something from the early 2000s, you might want to go see what you can steal from the era.