@noah Same, amount of hotkeys to learn the program to working degree and the fiddling with brushes is hard. I had that video of Ina using Krita and it details keybindings which I lost, it's lost on my HD.
If your tablet has physical buttons you can also use the command "xsetwacom set" to remap the buttons, for example Ctrl+Z:
$ xsetwacom set pad Button 1 "key +ctrl z -ctrl"