I am working on a tool to create tilable textures and other stuff. It features a node-style workflow to support non-destructive editing. I know that texture nodes is an upcoming feature in blender but I think it won’t be a complete overlap.
Project page: https://github.com/milasudril/texpainter
If you use *buntu 20.04, here is a ppa: https://launchpad.net/~milasudril/+archive/ubuntu/texpainter