I was going to ask the same thing. The pi really struggles with XBMC to the point where I've given up on it. A command line version I can control via ssh is just what it needs.
It says you need an html5 browser to play your music. Is there a plugin that can just play the music directly, so I can play via ssh and not have to kick off vnc?
You only need a browser. On the machine on which you thought you were going to run the VNC client, you open the browser and go to beets’s web UI. Then you pick some music to play, and beets streams it to the browser, which plays it on that machine.
If you actually want the Pi itself to be playing music, then you probably want not the beets web plugin but the BPD plugin, which emulates an MPD server. You can use any MPD client you want to control it – CLI on the Pi, one of the GUI apps over the network, whatever.
It says you need an html5 browser to play your music. Is there a plugin that can just play the music directly, so I can play via ssh and not have to kick off vnc?