This post spoils what happens in my Quake map. If you care about that, play it first.
I made another Quake map -- this one was for a map jam called Retro Jam 7, where we all spent 2 weeks making level design homages to the greatest hits.
The theme here was "Koohoo" or "The Castle of Koohoo" (2001) by Vondur. The theming felt very fresh for Quake at the time, taking notes (and maybe a few textures) from Unreal. The novel use of greens and blues, as well as the outdoor hub layout, contrasted a lot with the browns and reds of Quake 3 Arena inspired aesthetics popular at the time.
Of course, I figured everyone else in the jam was going to lean on those dark greens and blues, so instead I opted for a rosy morning brown type of mood.