Note: I will be tallking out of my ass here
One thing I don't get is the complaints about there not being enough "2D" sonic levels. Now, I haven't played a Sonic game in ages, but I remember them being pretty short. From what I have read, once you've finished you can skip the werewolf stuff and just replay the "2D" levels. Sounds to me that those levels are cumulatively about the same length of past Sonic games, so you're basically getting a full "old-style" Sonic padded out with some crap.