WowAce

One of the features I miss from baggins is the option to have sub-categories within your categories, E.G. you could have a stone and ore sub-category inside of a mining category. It would be nice to have this functionality back, but would probably be a lot of effort as I'm sure it would require a not insignificant re-working on the internal data structure.

In baggins there was also support for collapsing not only an entire category (as supported by famBags already) but also individual sub-categories.

This will imply indeed a big refactor on the addon's core. Right now, I'm trying to take it slow, have just come back so I'm not very inclined to do this kind of enhancements for the moment. But then, I can't speak for the future, who knows :). I'll put this on waiting until its time comes.