I saw you already had some comments about the difficulty and menu restarts, so I won't go into detail with that. I would like to point out 3 things that I think make this game tottaly stand out.
1. TOP NOTCH Aesthetics, absolutely gorgeous in it's simplicity.
2. Everything feels as smooth as it possibly can, very good job on that part.
3. First tutorial-like level is perfect in terms of introducing the player to the game, very fine choice in how to present the controls to the player.
One thing I would add would be more sounds and music, that would take it from S mark to S+ :)
Gameplay wasn't really my cup of tea but I was hooked (pun intended) by the visuals 100%.