The coin collecting mini-game is fun for a while, but it gets old very quickly. I'm in agreement with a few other commentors here that it really needs an upgrade whereby it can be done away with.
Level 19 is unnessisarily difficult: it isn't a puzzle, the solution is obdvious. It relies on split second timing and it is more frustraiting than amusing very, very quickly. If it's going to be hard it should be hard on merit of having an interesting solution; not timing and precise shaping.
i'm sort of glad people actually read... thats uncommon