Suggestion: this subitem (with #) feature will be nice for Tools, for User defined genres, too (and so on...).
Why?
Tools: instead of
Google, artist+song
Google, composer
...will be...
Google >>
Google, artist+song
Google, composer
Genres: instead of
Folk song, english
Folk song, hungarian
Rockabilly
Rock and roll
Rock later
Rock hard
...will be...
Folk song >>
Folk song english
Folk song hungarian
Rock >>
Rockabilly
Rock and roll
Rock later
Rock hard
Now I must to scroll Tools with little arrows, and genres too (fortunately, in genres works mouse scrolling).