> Once you start accumulating all the fonts you needed over projects, your Inkscape and Gimp become terribly sluggish on booting.
Isn't this an old Windows bug, where GIMP would recreate the font cache on every start? I don't think I've ever seen any noticeable delay on Linux. (I have hundreds to thousands of fonts installed.)
It boots fast, but many menu's and buttons will stall for seconds or longer while fonts are being loaded. There may be an issue for this in some bugtracker, I have not checked this yet.