Not a hard game even on the standard mode, except some of the timed boss challenges after you beat the game take some strategy.
Docking a star for the souvenir hunts. Honestly, they almost ruin the game. There were twice as many of them as there needed to be, and it would have been better to list them all out at once rather than having to go back to the NPC every time and then having to go into a level and replay the entire thing, sometimes multiple times.