Insidia
I love everything about this game except for how easy it is. There was not a moment in the game where I felt the need to second guess myself. I never had to take pause to consider where I should go, or what next must be done. All of the obstacles are easily avoidable and, although multiple paths are open to you, there is never any doubt about following the right one at any given time. You need to challenge the player, force the player to concentrate in order to progress. I did not need to concentrate while playing this game, not even to find all of the hidden switches. Of course, the design, atmosphere, music, and the overall style is definitely polished. The controls are smooth and sensible. But this is a game, and a game can be good even if the visuals and the controls suffer in quality. A good game feels novel, challenging and rewarding. These qualities are what is most important.
I hope this doesn't discourage you at all. I just figured you'd get more use out of concise, honest criticism than paragraphs of praise. I hope you continue to create platformer games :)