You could get this to work good if the unresolved issues with usertracks are fixed, but would this then be competition for RealTracks sales ? or would it bring more sales of Biab ????
With the PG templates you need Biab or need to read the pdf chords.
I could make up some that also have midi files that contain chord name markers and midi chord notes as well, these will then load into most DAWs to give the chord track,
mp3 tracks could also be included for the musician to play along to.
These can be a sticky post in the UserTracks forum.
You can contact session players suggesting this or put some post in the online collaboration/session musicians forums.
The musicians can upload a sample usertrack and work on donations or so many crowd donations to create a usertrack ???