For me the absolute killer feature for Gimp or Krita would be a way to save the editing history, which is currently lost with all the levels of 'undo' when you save in native format.
Versioning for image editing; I don't know how it would be done but by Jove it would be a time-saver.
Versioning for image editing; I don't know how it would be done but by Jove it would be a time-saver.