There's not much to say about One Piece: Heart of Gold. It's a mediocre-at-best story with terrible new characters and a paper-thin plot. The interactions between the Straw Hats feel off from the anime and they also feel less powerful than they should be after defeating Doflamingo. Luffy should have been able to defeat Mad Treasure in their first encounter, but for the rest of the story to happen he and the other Straw Hats needed to lose that fight. This doesn't even feel like a satisfying prequel story to Film Gold and probably should not exist....