"Button voting" can't be implemented anyway
The web interface to the BTS is read-only. You couldn't have "button
voting" anyway (and of course that would be a mess without requiring
registration, which isn't implemented neither...).
I guess the way to go with the BTS is to switch to Bugzilla/other
That doesn't mean the recent implementation of version tracking wasn't a
good idea. As long as there are people to work on doing all the rest... :/