that was awesome. I really liked the core mechanic and I think you've got the art of slowly building difficulty down pretty well. I think some careful adjustments would improve it, like having a little raised floor that stops the ball in the ball puzzle, or maybe have the ball stop when it reaches a really really low speed, because I got hung up on that puzzle (a puzzle which i thought was really cool and well-designed, by the way), but I got hung up simply on praying for the ball to stop when otherwise I felt I had solved it. If that makes sense.
but yes stick with this core mechanic or reuse in future games, because it's a winner for sure