Well he was definitly worse than Luffy, idk about worse than Roger, Roger murdered Squardo's entire crew, that's a kaido level of villany, but being worse than them, doesn't = Being evil, also the buster call if there really was one had nothing to do with Rocks, the world goverment summons buster calls to deal with every inconvience
He failed to take the throne of Mary Geoise, it’s okay for him to try to be king elsewhere. The navy was on to him, maybe they’re the wrong ones instead of evil?