As many people may know, Blender is commonly used on Linux. It is actually developed on Linux.
However, I have noticed that Blender does not have any major integrations with any desktop environments, which is a bit disappointing.
Essentially, my suggestion is that either through an addon or another method, gtk and possibly qt themes could be imported into blender. Obviously, a gtk theme would not address all aspects of the UI, but I think even if that even if the only functionality was to import the main colours of the theme, that the feature would still be useful.