This is a bigger one but might be quite beneficial for both players and iRealPro.

I bet there are plenty of musicians over here who can record all tracks cover of a song with their home equipment.

I'd love to buy a backing track, like Cantaloupe Island, without one instrument, like Piano, so I could play on top of it.

The only difficult part is how verify quality of the backing track.

I want to do it in a way that is beneficial to all parties, so it works nicely.

My solution begins with all interested musicians submitting an audio track. Also all interested parties can choose toi buy the audio track. Public is to rate quality of audio tracks by arranging them in (their) priority order. Money is divided between submittors, quality, and iRealPro.

This solution is still bare but I think there's something in it.