It would be lovely to see a return of RGB color sliders, in some fashion. I think it was possible to hose yourself - leading to support tickets - if the same color for foreground and backround was chosen. The preset “color themes” ensured this couldn’t happen.
Check out my “what da heck colors is THAT” screenshots from 2012 in this other thread.
Keep the color themes, but let us customize with a color picker: 16 to 32 shades, from grimdark to dayglow orange would make a few people happier.