Thank you for detailed response! I feel honored when I get response from pro 
Yes, these are the right questions. Also I was thinking about that…
IMHO the best solution would be to have possibility to save/load Brush Preset XML (something like for filters) in every moment (realtime brush preset state). That way you wouldn’t be forced to create new brush preset for every tweak. If I could vote for one Krita feature, that would be definetelly “Save/Load Brush Preset XML” (or json or something else).
PS: Switch to Alternate Version of Brush Plugin (also has a nice video) is trying to solve similar problem, but again, Brush Presets get flooded with brushes quickly. So the only solution is like @Grum999 said, pack them in bundles and activate/deactivate bundles.