Almost perfect !
It's almost a perfect song ! I love the idea and how you organized your patterns. I also enjoy the little things like those heavy piano chords from times to times, or the choir in the Tetris theme.
I do have one issue with the electric guitar though. Don't get me wrong, I love rock and everything, but I find that the guitar is like an intruder. The idea of using it is good, however it's too present in your mix, and I think :
- Or it should not be there,
- Or the volume should be lowered during the Tetris' theme patterns.
Also the guitar, which has a somewhat rough feel that makes a rather brutal contrast with the rest of the instruments that are somewhat calm and soft.
Except that, it's a great idea I love it, and you did a good job ! Well done !