Build: Personally, I don't think the build is very good. Besides it being incredibly unoriginal, it's very bland. It's just a floating nether fortress with some parkour around it. We expect maps to be more creative, attractive, and cohesive.
Parkour: The parkour was fitting for the medium difficulty in both length and difficulty, but it did not have very good CP placement (for example, the first CP is incredibly long, proving to be very hard for the difficulty). Furthermore, the parkour itself was rather uninventive. A lot of the same jumps were used over and over again, which prove to make the map very boring to do. Try to be more creative with your parkour, don't be afraid to experiment!
I hope you take these criticisms into consideration when submitting maps in the future, good luck!