There will come a point during your time with Rayman Legends where you'll run out of ways to express how much you enjoy it. By a few hours in, you'll have exhausted every synonym you know for "pretty." A few stages after that, "fun." By the end: "challenging.
Sheer volume of content; Impressive level variety; Fantastic visuals and music
Initially confusing interface; Murfy isn't always welcome; Chaotic co-op with three or more players