Display of AC/DC as AC, should be AC/DC

[timster]

This sounds like it's something to do with what mp3 coding you are using. I'm no expert but I think ID3v2.3 handles multiples better (although my mp3 converter created an artist directory up to the slash, the actual tags in them do contain the full name with the slash, and iTunes shows them correctly). So, perhaps do a batch convert all of your mp3s to ID3v2.3? Rather than flac (cos then you're just padding it out with zeros).

Having multiple artists in an album isn't a problem and shouldn't cause misery. If they are compilations then Various Artists as the album artist is the usual thing to do. If not, then the album artist could be the main one (eg. Lump - it is actually a collaboration between Laura Marling and another guy, can't remember right now who) but I have the Album Artist as Laura Marling, and the track artist as both her and the other guy. The album artists could just as easily be Lump).
Or guest artists - so the album artist could be Fred, and the tracks are by Fred, or Ginger, or both, or even George. Doesn't matter.