Tiny things:
Add some trim to this, and use a higher-sided curve for that corner + smoothing groups to smooth that out and look extra sexy. Probably will have to adjust lightmaps a bit on the sides. It also looks like you just took that white platform and rammed it through the wall. It's a bit too continuous, make it look like it belongs there, not just that you forced it in.
Totally get that this ramp is supposed to be here, but it looks REALLY out of place and totally awkward visually. If you can smush in a stair or something there, it could look a lot better.
Trim on the bottom left isn't even and is rather noticable/ugly. Try your best to get that thickness equal everywhere, or have a better transition between the sizes (not just a brush that starts small and ends bigger).
These I-Beams (?) are way to thin looking to be even remotely structurally sound, they also look really out of place in a concrete environment. Either chuck 'em and do something else with that ceiling, or make the ibeams look more like they're actual support features, than just a piece of metal on the ceiling.
EDIT: Also, last image, the lighting on that pipe is too bright for the area it's in, should be darker. Maybe use a lighting origin?