Thank you for the suggestions! The planet should always make exactly one full rotation, regardless of number of frames. If you increase the amount of frames it will simply make the animation more smooth, but still one rotation. You're right on the amount of white space for a star, it's due to the way the generator is programmed. I haven't really seen it as a problem, but if it's an issue I can try a fix.
Thanks for the feedback, appreciate it!