I don't know how much this feature is wanted but we at least need an option to browse by tags. Folder structured browsing is really counter-intiutive when every other player does the opposite. You can't just change your folder structure and names if you use torrent, have huge collection etc.
Now, i know sindre will never add this to original subsonic and musiccabinet is getting horribly outdated. So if you think you can add this feature some day please let us know.