Yep, you can set BPM at the rackspace property level
Within each preset ?, not just globally, that’s awesom!
Not (directly) at the variation level but at the rackspace level. Having said that, since the BPM can be changed from GP Script (or via OSC) you could easily respond to a “Variation Changed” callback and adjust the BPM. Or, you could put a widget on the front panel and have a GP Script callback respond to the widget to change the BPM. Then if you have multiple variations, the widget can be set at each variation and then it will be remembered.
Lots of possibilities