I gotta admit, the first levels felt poorly designed. They were waaaayy too easy, and the solution was blindingly obvious. Some of the levels in the middle were ok, but that final level was incredible. That was a real puzzle, one that really tested the mechanics, and had a super surprising solution. You need to make more levels like that last one, it was so much more interesting when the solution was hidden, and required you to overcome seemingly insurmountable obstacles. Brilliant design on that last level. Great job with the game!