Can people who feel similar share what metadata do they miss the most? Maybe I'm a caveman, but I feel mostly satisfied with artist/title/album, plus maybe the year at most. I came to use filesystem directories for genre/mood tagging and then also artist/album obviously. It's crude, but usable and easily portable. I'm not claiming this is all one can wish for, but I'm curious.

For this kind of library I found Audacious (minimalistic, supports Winamp skins) and QMPlay 2 to be good. The latter supports and remembers your folder tree, has a very cool widget system and can be also used for videos (music or otherwise).