Rayman Legends is a good game. There are only a couple of things that drop down the score of this game.
1. The game doesn't have online coop- Why don't most platformers have online coop? There's no reason for there not to be online coop, since every argument against it could also be applied to fighting games which are online.
Some people will blame it on lag when playing online. Like I said, that isn't stopping genres such as FPS and fighting games.
2. The Murphy mechanic- I was playing this game on PC, but Rayman Legends was designed as a Wiiu game with a mechanic in which you would do various things with the touch screen. There are a couple of levels that are much more challenging with the predetermined AI mechanic, one level in particular took much more time than it should have.
3. The Vita version has less levels- Now I didn't play the game on Vita, but I've heard that the Vita version has less levels on it. I wouldn't normally complain about something like this, since the game is cheaper on Vita, but the devs themselves said that the Vita port would include all the content of the other versions.