Beets vs Multiple Library Folders (and other 'n00b' things)

Instead of having lots of separate beets libraries, I think it would be better to use our metadata-based naming schemes to separate the various directories. You might create a flexible attribute called $category, for example, that might contain either mine, brother, downloaded, etc. Then you can use the paths: section of the config to sort your music accordingly.

Yes. (This is an acknowledgement that it’s very difficult to tell, just by looking at tags, whether they’re “good.” It has to look the music up in MusicBrainz to tell.)

If you mean the -A flag to the beet import command, yes.

Yes.

Do you mean an m3u file? No, I don’t think that’s something that any of the plugins currently do. But it shouldn’t be too hard of a plugin to write.

My recommendation to you is to try things out on a small chunk of your music—after making a backup! It can be really instructive to see how things go when actually running the import under various settings, even if it’s for a small amount of music.