Inspired by this blog post by the krita legend David Revoy, I too turned a cheap USB numpad into a shortcut keyboard. This is quite intuitive to use, even if I've just been a couple hours at it.
This thing is really useful when you draw on a digitizer or are on the go, the picture on the blog really illustrates the vibe, though you'll rarely see me drawing pixel art at a cafe.
Anyway, here it is, in all its glory!
The post explains how to do it, I used a dymo for the key stickers but I may have to look for a more permanent solution since the stickers are already peeling off. I want something easy to remove until I settle with the locations for all the keys though, so it's fine.
At first I found it was a bit annoying how the method shown in the blog (uses hwdb for key remapping on linux) doesn't allow binding things to key combinations, but then I realized I'd much rather have dedicated Ctrl, Shift and Alt keys because aseprite uses all three in various ways, so it's much better that way anyway.
Also to my delight, the numlock key is not special in any way and can be rebound just fine. It will even stop the led from flashing!
To finish the build, maybe I'll find someplace online where I can order custom key stickers with my own images and draw custom keycap icons in my own style, that'd be cool.