Hello there, recently discovered this great software.
Seen artists use bluetooth controllers in apps like Clip Studio for quick access to things like Undo or tool switching, thought this would be a good addition. I find a tiny controller like the 8bitdo zero fits nicely and it tends to be a bit nicer on my wrist than a keyboard, while not requiring any flat surface.
Some controllers have keyboard mode so even just keyboard shortcut customization would help out hopefully.