About Leo, I will say as good as he was in INception...Cobb is a much less complex character than Teddy Daniels. Shutter Island lived or died on his performance. He was much more the center of an ensemble and the bulk of the weight of the movie lay in the director's hands. Also, the scene where SPOILERS Teddy/Leo remembers finding his children floating dead in the lake behind his house and has to collect their bodies and then mercy-kills his wife....as hard as it is to watch, it may be the best scene of Leo's career thus far.
On the Lynch thing. She usually plays similar characters. But Sue Sylvester is quite different from the character she plays frequently in Christopher Guest films or in Role Models, etc. Sue is a surprisingly multi-faceted character who has different tics than what we've seen of Lynch before now.