To elaborate on modding: REFramework works if you include proper WINEDLLOVERRIDES parameter. REFramework scripts I use all work perfectly. The exception comes with texture/font replacement mods. While installing them isn't an issue (Fluffy Mod Manager can be just added as a non-steam "game" and works perfectly fine from there, not all mods installed in that way seem to work - replacements to the loading splash screen and game font refuse to load (I had one instance where fort replacement randomly worked on a launch, but it stopped working again next time). Replacers that load later into the game, like HD Hud or changes to monster icon seem fine. In the end I'm not even sure if this issue is Linux specific or not. (Font replacements via .pak mods do work though)

Overall though this is likely a non-issue to most people.