I am not all that keen on [bonusbar:x] either, especially since the whole bonus bar system has been revamped to be override bars. I am all for keeping things consistent. But, if it is easier to fix the [bonusbar] conditional than add new ones, it would be better than the current state of addons needing to react to UI changes in a secure way.
I have not seen anything on the beta forums yet. And quite frankly, I have been a bit out of touch on how and where to best make UI suggestions that will reach the UI team.