I think after the big 32 > 64 write a total re-write will be down the track away. But the bar to bar re-gen that has been requested for years would be good to see, when I used RealBand all the time this is what I used endlessly as it was so simple just highlight the bars (or beats) of the track and re-gen.
A lot of users prefer Biab over RealBand because the tracks are generated direct to RAM so it's instant, but we may just get that feature in the Biab Plugin now.

Here's a way that the current MultiRiffs can be improved, with just a bit or programming.
:
Here's the flow if you're in a current song:
1. When you select MutiRiff, it will ask if you want your master
(all unmuted tracks) for the MultiRiff Audio guide track.
If so BB will render it to stereo wav with Audio muted. BB will save current song frozen.
2. The rendered Audio master will be loaded into the MultiRiff session. A riff will be chosen by soloing or selecting in a dialog.
3. The current song will be restored, frozen tracks loaded back into ram and the Selected Riff will be brought back into the Audio track.
4. If a section needs a re-gen or new section added it will go back into MutiRiff again, gen that section.
5. Back to original song it will paste or paste overwrite the new section into the Audio track.

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