Thank you for this in depth feedback, I tried to make it juicy and put in a lot of time into the music and SFX, so it's good you found those as strong points.
Better keyboard controls will certainly come should this game continue in development. I'll probably continue to support the mouse controls, but certainly Q&E/F would be a good start. Definitely want to consider allowing the magnets to pass through each other should it continue, biggest reason I didn't do this currently was it's a little bit tricky to set up with the tile movement (which I used for the magnets) , and will certainly get worked on should it continue!
Thanks for playing and for all the feedback! :D