Would (a sample way of) disabling midi send/midi listen from BB to Aeros work for the first case? Could be a software feature on ether.
Might try adding hardware switch box to add to the midi cable. Wonder about the behavior with the midi clock dropping out , but probably fine.
For the second two cases, you should be fine today. The current method of connecting midi is for Aeros to be a slave (midi in only), so nothing you do on the Aeros affects the BB.
WRT freeform: Yes. I tried having a blank song, The idea was to run it silently for one bar on the first track before the song started, then when I wanted to record I switched tracks mid song. It worked, but the tempo needs to be close to my freeform tempo otherwise I run the risk of being out of sync at the end of the recording. An option to easily switch off the requirement for a tempo on the fly would be great. By on the fly, I mean without going into the global setup of the Aeros, hence my suggestion of a song by song setup. In a live situation you don’t want to be mucking around with global settings.
With the blank song you can easily delete everything with the start/stop switch when the song finishes so it is ready for another number.
Agreed that to run the BB on its own, a way to quickly disable the midi send on the BB would work, because again, in a live performance you don’t want to be mucking about wth global settings between songs. A blank song with a pre-recorded, but silent, 1 bar length first track is the current workaround for this, I think.