Nothing in 2 really comes close to waterloo or the milk man though. I think milk man wins by default just because waterloo commits one of my biggest game design petpeeves: using a mechanic only once in the entire game. Its the only level where you need to ledge grab, and only in one part. Why?
Milk man is great though. Theres tons of interaction and attention to detail in thst level, and the 4D mazelike nature of it is a blast to play around with the levitation. 11/10 level.