Not a painter myself but I know some folk here are. Might be of interest, so fyi.

https://www.giveawayoftheday.com/luminance-studio/

OK; dabbled with it some (and it took some time for me to figure out how to get the symmetry thingy to work. lol). Very slow on my aged system, though. Has some filters that I've not really explored much but very promising so was worth the install. Can't beat the price (today anyway) either. Would have shared with you the transparent background PNG file but it was over 5.1MB so settled for the gray background. lol