I appreciate you want one application to do everything, but that doesn't preclude using other tools as necessary. You could use a separate tagger to deal with those. I don't need to use it much anymore, so it may not be the best choice, but I use
MP3tag for whatever MC can't handle... "Mp3tag supports online database lookups from, e.g., Amazon, discogs, or freedb, allowing you to automatically gather proper tags and cover art for your music library. Mp3tag supports Advanced Audio Coding (aac), Free Lossless Audio Codec (flac), Monkey's Audio (ape)..."
Understand that the actual tags in the media files provide the means to exchange the information between programs. So, for example, I use MP3tag like this: Select the tracks for which no information is available from YADB. Right-click and
Send to MP3tag (which I've added to my
Send to menu). Fill the information using one of the databases MP3tag can access, and save it. Back in MC,
Update library (from tags) (i.e., read the information into the MC database). Finally,
Submit Track Info to YADB—so the next guy whose 4 month old is keeping him awake all night catches a break.