I loved the Boilerworks level, wasn't even there for too long and the gimmick was fairly straight forward! Don't think I've come across a weak floor yet, and I'm 2 floors away from the end too!
Another thing I don't like about this game is the, what I feel like, constant use of "you're not done when you think you are". It's really tiring and I despise that kind of design. Takes the fun and the feeling of advancement out of it. The