Not tried beets (this thread only now made me aware of it), but adding a +1 for Picard
I let it run on a huge chunk of my music and apart from a few tracks it thought should be in compilation albums, worked really well.
After the big sift, I basically just run it on new stuff when I get it...
Sometimes I use Puddletag to fine-tune some data.
I find most new things I get from Bandcamp, etc are in MusicBrainz, so not much editing required... although I have spent some time over the years carefully entering some older, more obscure music.
+1 for XMPP
I'm currently using a public server until I get my own (Raspberry Pi based) Prosody server running
Never had a missed notification / message and video calls are great too... even Grandma can use it
Using Conversations (Android) and Monal (ios)