Something I've mulled over in the past is what a market-driven pricing model for streams would look like. Newer songs are generally worth more than older songs, and lean-in listening costs more because the user actually wants to hear a specific song, while in lean-back listening, anything with a similar vibe works.

It's probably a good thing it's hard to pull off because you'd see Taylor Swift streams going for 10 cents and aspiring artists paying you $0.0001 to listen to their work in the background.