@rysiek RE: #FOSS
Ah, you did mention UI/UX issues. And documentation. That is the main thing a lot of these free programs are lacking. Blender3d has fairly good documentation, and if you are a shortcuts person, its amazing for that.

GIMP has been a struggle to use (Broke off into Glimpse). I only program in python, and I am a beginner at that. And GIMP has been confusing to use, with tablet driver issues.
Writing drivers is insane programming work tho.