The camera made me motion sick. Regarding the level design, I must ask: what gets added by splitting the gameplay across 2 characters? During the level I played, I didn't really see anything where if the wall in the center wasn't there, I couldn't have done with only one character. Any time a mechanic is added to a game, ask yourself what it really changes. If the answer is nothing, then it's what I would call "fluff"
(There is a chance I didn't get far enough in your game to see the interesting aspects of the mechanic. If that is the case, I apologize, but the camera has given me a headache and I'm going to go lie down now)