+ : Positive
- : Negative
= : Neutral Suggestion
Gameplay
+ Line based puzzles is unique and cool mechanic
+ Good difficulty ramp and progression through levels
- Most of the puzzles to me felt too obvious - they didn't pose enough challenge to be interesting, or at least didn't subvert expectations. I noticed that each puzzle did have an "obvious" solution which would turn out to be incorrect and a real solution which was the obvious solution changed very slightly. This is typically good puzzle design imo, but the two solutions were immediately visible to me from the onset of each level. It might be due to the limited number of variables with your current mechanics. But hey, puzzles are extremely difficult to design, and while yours didn't hit the mark for me, they definitely are going in the right direction.
Art
+ Good Assets
+ Like the added scenery for each level
+ UI clean and understandable
- While parts are individually good, the game is missing a strong overall aesthetic, if that makes sense
Sound
+ Has SFX for everything! Too many games skim on sound
= That being said, I don't feel strongly either way about the sounds being used. While they definitely add to the game, I think you could be more creative in this category.
Bugs
+ None Found, Good job!