For my first suggestion, I was just thinking that it would be neat if we got some more brushes to choose from in Oekaki. I also use the Gimp program for just simple photo editing and i would love to maybe see some other brushes similar to these that we can pick from. Specifically i would LOVE to see an "X" shaped brush. It would be amazing for star flare and other glare effects!
For my second suggestion, I would also like to suggest tweaking the brush cursor icon so that it's the same shape as the brush that you are using. (round cursor for a round brush, square cursor for a square brush), as i always have the most difficult time judging where corners are going to land precisely when trying to use square brushes at the moment with the current cursor setup.
Third and last suggestion, perhaps also have an option that we can turn on / off so that the cursor still remains visible as we are making brush strokes instead of disappearing until the end of the brush stroke is finished.
Thanks for hearing me out on these. c: