Current scratch pad in Brush Editor is good for test new settings of brushes but bad for editing brush icons. It isn't multi-layer and where available tools is very limited.
I suggest that we should have brush icon library where we can store foreground and background icons from selected areas on canvas or external images and create new icons for new presets with icon resource of the library.

https://community.kde.org/Krita/Brushes_Preset_Preview
https://bugs.kde.org/show_bug.cgi?id=322677

As much as i love krita the way brush icons are managed are my biggest pet peeve of the program. I happen to be one of them artists that is a brush tweaker.I only use one or two brushes on a piece of art. So im constantly modifying a brush through out a piece of art. I know several artists who are like that. But between using photoshop and clip artstudio i developed the habit of constantly overwriting a brush through out a piece of art.. its not uncommon for me to do this 20 times through out a piece of art. So im constantly having the misfortune of losing the icon because i forgot one extra step which happens due to health issues that have effected my memory somewhat..ive gotten to the point now were i don't even bother making icons for my brushes cuz ill just end up losing it anyways because overwritting a brush requires having to load the icon up every time. So i would totally be supportive on a revamp on how icons are handled in krita..

Reworking the brush editor and brush management has been suggested previously by others, including by me.

scottpetrovic wrote:Thanks for the feedback. I think there are a lot of people, including the developers, that want to see the brush editor improved. There is a lot that can be improved, but it will be a pretty big project. The "editor" does quite a few things, so we need to break down everything that it does and figure out the best way to organize everything. It takes up too much space on the screen and has a pretty inefficient UI.

I can see this area being revisited after a lot of the text and vector work gets done. That is also a really huge project that is adding a lot of things that currently don't exist.