As a puzzle game lover, I really loved the concept. However, I feel that sometimes I solved, or had to solve, with luck of the draw. The larger levels also tend to feel tedious, and puzzles feel solved in small chunks rather than as a whole picture.
I agree. This game is very unique, and has a great idea behind it, but there are things (most of which you mentioned) that could be tweaked to make the gameplay a bit more enjoyable, and not as tedious.