Sucker punched!
I'll admit, in the first couple of levels, I thought this game was going to be all flash with no substance. There was no challenge to it, and it took me a bit to realize that it was acting as a sort of tutorial. That's a minor gripe - this game should have either a set of instructions or a tutorial. Learning as you go is a bit annoying in what's supposed to be a puzzle-solving game. Add some challenge to the first levels.
The only other complaint I have, and what lost you the point was the the overused medals. Giving gold and silver medals that don't actually mean anything in rankings for every other challenge is as irritating as achievements for accomplishments that aren't. It was an unnecessary ego-stroker.
This IS an excellent puzzle-solver, and aside from those relatively minor issues,
there's nothing it really needs for improvement, IMO.