Very cool game. The setup is very nice, I especially like all the tiny details put into it. It's a good take on the theme. The gameplay is good, i like the fact we ends up learning the skills pattern as we go through the layer, making some kind of meta progression.
I tryed the Letter-Number way for the control, it's definitly more challenging. On the other hand the arrows gets a little bit repetitive.
Still it's a great concept and well executed. Well done!