This is a seriously awesome planet generator! However, I have one problem with it: the exported planets spin way too fast!
When exporting as a gif, I have to get to the 1000 frame count to get something that doesn't spin super fast, and even then I wish I could get it spinning slower at a nice framerate. It would be really awesome if we had the ability to export a 1/2, 1/4 or 1/8 rotation for more cinematic shots where the planet rotates slowly but not for a full cycle.
All in all though, awesome tool. So fun to mess around with, great job :)