Hello __Sage,
Unfortunately, I will be
Rejecting your map.
The theme isn't original, as there are many musical instrument related maps, including piano maps. Please refer to the document in this thread -
https://manacube.com/threads/parkour-list-with-theme.20194/ to make sure your map idea is original.
The build isn't great, as it does feel quite flat. I know you did add the music notes around it for decoration, but it would be great if the main build itself could have a bit more shape and depth to it.
The parkour is very repetitive. You did use a few different types of blocks, however you did group them a lot. What I mean by this, is that you would have a sequence of just ladders, then just normal blocks etc. Try to mix up your jumps a bit more throughout your map, as well as experimenting with a larger variety of blocks and items, to create more original and enjoyable jumps.
There are quite a few floating jumps. Try to implement the jumps into the build more and avoid having an excessive number of jumps floating around the build and the void, as having a lot of floating jumps can make your map look quite messy.
The difficulty is good for an easy/medium, and the length is good for a hard map.
Thanks for submitting your map! I hope to see more maps from you in the future.