With classical music, standard tags don't cut it. So I just do the best I can with the tags, and then I rely on my own folder sytem to organize the tracks, then I browse by folder.
My Beethoven directory has >1000 tracks and Bach God knows what. So I have to do Beethoven>Piano>Sonatas>[Artist]>Moonlight Sonata... Then I have 5 artists playing it, there's 15 tracks right there. There are 32 Sonatas. Then quartets, symphonies, trios, concertos, overtures, etc. Standard tags can't handle it all. Sonos only uses standard tags.
I want to use folders as the main organization then add tags to fill in the extra info. But I can't change the Sonos app to display composer instead of album artist tags, etc. Eventually a more configurable player like foobar will take over when I go from Sonos to PC based.
I like having the music in folders so I can find it easily if I want to rip from flac to mp3 or apple lossless for a portable player.
Good idea backing up the music on a separate drive. My NAS is making funny noises. I think it's the fan but I gotta check it out today.