I have three ideas for Play!
1: Align the music library and playlist vertical instead of horizontal –
Music library left and playlist right. This will make it more logical to use..
2: Ad music automatically when the playlist runs out. Nobody likes silence
3: Ad kiosk mode/full screen option with only “ad to playlist” option available. This is great if you are having a party, and don’t want people to change song every half minute. Use a key combination to get back to normal mode.
Hope you like the ideas.

Jakob Rindom Madsen. Denmark