Think is easily my favourite game of the jam, I've been playing it for the better part of an hour.
It's very well polished in pretty much all regards, the main mechanic is clever and has been explored in a variety of ways, and the small bits of humour are really great. The walking mechanic is really nice and gives a really great twist to the problems.
Most of the levels are excellent, with some really great "Aha!" moments, though as you've said there are a couple which could have had the difficulty turned down a notch.
I also love the main menu :).
Really superb job guys.