I've played this game to exhaustion and this is what I've determined for bonus stars.
world 1: 2, 3, 6, 7 (hard but doable), 8, 9, 10, 12, 13, 20
world 2: 1. 3. 4. 8, 9, 10, 11, 12, 13, 17, 18, 19, 20
also @technic 160 stars isn't possible that would require completing every stage under par... including the ones in which par is 1... you know, which would require 0 moves to finish under.
There's important things we need to know!
Who started the conflict?
How many others survived?
Probably a dozen other questions I didn't think of, these are valid things to ask!