The room is looks very bland and depressing. The textures are really dull and everything blends together into a brown mess. Improvements to the lighting setup may help.
This is awesome! my only crit being the backgrounds are to colorful and and close to the player colors, they blend into the bg a lot, which could be considered unfair imo.
The bleeding? Polypaint is vertex painting. The vertices on the borders of 2 groups are sharing 2 colours. Polypainting requires a dense topology to get a crisp edge.