Really nice idea! I'm not much of an Idle Games person, but did have fun trying different combinations of Planets & Orbits in order to find an efficient strategy. The visuals are quite nice to look at. Some sound effects (e.g. when buying new Planets) would be nice, and it would be cool if the different Planets had different attributes to make combining them and their Orbits more complex. Also, dynamic price rates for the Planets might be something to consider. All in all this looks like a great foundation for a fun game!