Fun little game, and quite challenging. Clever mechanics and level design. The addition of magnets really kind of threw my my mind through a loop trying to plan how to go about solving some of the later puzzles.
One thing I think is underused was the wires. I recall only three puzzles (maybe) four that make use of them at all with one of them (level 22) being quite challenging. I would have liked to use wires in conjunction with metal blocks and magnets. Plus bringing all the different puzzle elements together in later levels would bring more of a sense of escalation. That the puzzles are getting more complicated in addition to just becoming trickier.
One area that really could use some work is the 'physics' of the player character. Fairly often I found him walking half through blocks or somehow pushing a block despite not having actually touched one. This kind of thing just added unnecessary frustration. If you do try to fix this either in this game or for a new one note that in this game the 'collision box' appears to be slightly down and left of the main character letting him clip walls and blocks on the right and top sides.
All in all I thought the puzzles were very well done and very challenging, but definitely possible. It's a good concept and it leaves me wanting more. Thanks for the entertaining experience.