It would be a nice addition for Plexamp if self-created playlists could also be manually modified in various ways. Now you have to manually drag songs in self-created playlists up or down to create your own order. It would be nice when you add a song to a self-created playlist that this song comes to the top of the list and not the bottom of the list.
Sorting self-created playlists by numerical, alphabetical but especially time of added so that new songs always come to the top of the list makes it so much nicer to work with Plexamp.