You should check out Cesium. I've been using it for the past couple of years. It accesses your music library, so all your music and playlists are there. You can play by album (and shuffle the music) or even play by artist (and shuffle all songs by the artist). You can even play by genre if you so desire. Of course it provides all the typical music queue management facilities as well, but I don't tend to use those too much. I like it's extreme simplicity.