I suggested that in the RapidComposer forum and it was just added in a short time.
RapidComposer Strum Pattern Generator can generate just about any strum you need on your virtual guitar, it can combined finger picking and strumming to patterns that can be saved and use over any chord progression, you can set the mutes to any keyswitch or velocity. The keyswitches are saved with the patterns.
RapidComposer also has a VST version that can be used in Biab.
Patterns can be shared with other users. It will import BB Chord Output track, you can fill the track with the same pattern.

But sure if PG made one for Biab it would be great.
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