> It also let you sync through your own server rather than Mozilla's which I don't think the new version does yet

This is possible with the new version, but it's not (yet) as simple as it was with the previous one:

   https://docs.services.mozilla.com/howtos/run-fxa.html
   https://docs.services.mozilla.com/howtos/run-sync-1.5.html

(edit: actually IIRC there's an open bug around allowing android devices to use a custom sync server; desktop devices definitely work fine with it via some about:config settings)