It would be nice if Apple allowed the Apple TV screen content to mirror back to your phone so you could control Apple Music ie. listen to Apple TV via WiFi without using a phone or iPad via airplay. Which drains battery etc. Or if when using airplay for music from iphone and a track is selected, that Apple TV could stream the Apple Music song from WiFi (on the Apple TV) and use the phone simply as a (smart) remote with an interface. Currently the Remote app is limited ie. can’t visually select a new artist, playlist etc and it’s somewhat slow to respond especially on Apple Watch.