I have Rhythombox on all my work and personal work machines(laptops) and I keep my music in ~/Music folder. 25GB of music from here and there, last 10+ years of music. Lots of them rated. And when I have to change laptops I lose all my playlists. Not anymore. Rhythombox saves all its data in ~/.local/share/rhythmbox and I copied rhythmdb.xml to new machine. One would say, why not copy home directory. Well, why would I copy home directory when most of my items are either on Google Drive or browsers have already synced them. I just copy Music and Rhythombox data files and am good to go. Yey!!!