Wym not photo editing? You can do everything aswell in Krita. Changing hues, retouching, selection, layers, saturation, tone balance. All there.
And you can most definitely use it for pixel art. Even if you don’t want to use Krita there exist paint.net, aseprite, piskel or pixelorama. No need for hundreds of dollars for PS.
I believe working 2-3 days a week would actually be enough and with the right organization method would allow even crucial 24/7 positions to be manned (like nursing and care staff). Plus you’d basically never be understaffed because you’d have lots of backups.
8 hours a month sounds a bit too utopian to me.