Have the options of the followers of a playlist to recommend songs they would like to have added. And give other followers the chance to vote if they would like those songs in the playlist or not. This would still keep the control of the playlist under whoever owns it, but would allow some community participation.
Updated on 2020-02-11
Because this idea has not reached the 100 votes per year quota to stay as an active idea, I am marking it as an inactive idea, feel free to re-post your idea if you are interested.