In public playlists, the additon of a "Notes" field with each track could prove useful. The user who added the song may want to say a few things about it to those listening. Only the person who posted the song, whether it's the playlist author, or another user adding to a collaborative playlist, can modify the "Note" on a song.
Example: You create a multi-genre playlist, and want to make sure listeners know the genre of the song they are listening to. The "Notes" section would be a great place to lable that.
Hello! A similar idea has also been suggested here:
Add your kudos and comments there please! 😉