00:56:499 (56499|7) - I think this note should be moved like 4 columns to the left to match the descending pitch relative to the couple notes before it
00:57:332 (57332|6) - Might not be necessary to have this note since only the piano is mapped in this section
01:50:915 (110915|7) - picking up from an off beat like that is really awkward, and I can't see a beginner being able to hit that well. I feel like a note at 01:50:665 would make hitting 01:50:915 (110915|7,111165|7) - much easier, but then hitting 1/4 for 01:50:582 (110582|2) - into 01:50:665 would be hard too...
I'm not too sure how you could go about changing this, but I do recommend you try to make it easier to understand. It's quite off putting as you're following most of the standard snares and drums, but then there's a sudden gap on the beat while the off beat notes are still there.