Great take on the theme! The chords you get with more planets are very pleasing but a little bland in levels where you only have one or two planets. Maybe when you complete a level or you're close to doing so, more frequencies could be added to signify that you've brought harmony/balance to the solar system (at least for a few seconds ;) ). I also really agree with mgiuca's feedback. Sometimes the game can get a little frustrating and it's a bit difficult to get the orbits you want but it's also very rewarding when you finally make something that works.