That’s a shame. I would have liked to get my entire library updated just as I want it (as of this particular moment…). I guess it’s still more feasible to get beets to fetch more tags than it would be to make Picard support large amounts of files.
I’m not sure what you’re saying about beets recognizing less tags. Wouldn’t the flexible attributes solve that problem?
You have some interesting ideas, though I’m not personally interested in any of them save from tagging 
And maybe the last two. I should look into writing beets plug-ins.