When I created this Control Bar.
I used a program called Sketchbook Pro7, which I have a perpetual License for, they also introduced subcription in V7 and Perpetual Licenses weren't an option in V8. Yesterday I installed the wrong V7 on my new laptop, and it wanted to update. When I updated, it told me the V8 is now free.
I use this a lot, it does layers and transparencies, with blends between layers. It's friendly and approachable. V8 allows user brushes, with free downloads as well as some other little features. And now it's free
https://sketchbook.com/