I think this will be difficult for LLM vendors to implement in the near term, as the cost of switching vendors is near zero. If vendor A implemented ads, preferential treatment to things, and it was very evident, switching to vendor B would take almost no time.
Most MIDI keyboards aren't really made for piano performance or even really for piano practice. If you want a MIDI controller for this reason, I'd recommend going to a music store near you (if applicable) and playing a few and feeling the keys and go with the one that feels nicest for your budget.
I would love to see the text you're working on also be on the review page. I also would love my text to persist between going back and forth from the edit screen.