Hi, here I'll try to explain a simple concept of fast switching between brushes, and a possible solution to known eraser question.

Krita is unique in a way of handling all the brushes as a single tool. If you look at other programs, you will find that eraser, pen, or blender brush - are separate tools, with their own hotkeys and presets. Its pretty handy to switch between them. You press "e" for eraser, "p" for pen, "j" for blend, and every time it returns you to the last selected tool from their category.

This is a lot faster, than picking two brush types, and switching between then by pressing "/".
Sure there is ten brushes plugin, but what if your picked brush wasn't assigned to a key, and you want switch back to it from assigned?

So here is my suggestion: a possibility to assign brush tags to hotkeys, as if they were separate tools.

Hot it works:
You assign tags in a same way you do in "Ten brushes" plugin.
For example we have:
Erasers tag - "e"
Smudge tag - "s"
Pen tag - "p"
All brushes - "b" (if it possible)

Pressing one of this hotkeys will switch brush preset docker to assigned tag, and to the last picked brush from it. If there wasn't picked any brush before, then just pick first one.
This will help quickly switch between two, and more brush types, with solves lack of separate eraser tool. But remembering last picked brush from a tag is essential.

I am not touching the tags part until the resource management has been fixed, because right now tags are really flakey and I cannot foresee an easy way for someone to select a section.

boud is however rewriting the resource management, so he'll have to comment about whether this is at all possible.

I'm not at the moment actually working on gui changes I wonder if I should put this on the libkis api todo list, though.