A simple, and obvious addition, but it shouldn't be too hard to add, and would be beneficial. It's just one of the tiny things that will help smooth Zone out. It's also been bugging the crap out of me.
Basically when you're on the planet select screen your cursor loops... Example:
You're cursor is on Irica, you press DOWN, it loops back to the beginning (Alpha). It works the other way around too, if your cursor is on Alpha and you press UP your cursor goes to Irica.
See? Simple