Build: The build is not very good due to a variety of reasons, these being: unoriginality (as it's just bigger versions of bookshelves and an enchantment table), poor detailing (they could definitely look a lot more like the blocks if you put in a little more effort into them), and bland shaping (there's no dimensionality to the build, it's so square-like).
Parkour: The parkour was definitely hard enough for a hard, but it felt too long. You should cut back on a couple of jumps. But, the main issue I had with the parkour wasn't that, it was with how repetitive it was. You used ladders and fences way too much, it just got incredibly boring to do. Make sure to use a variety of jumps/blocks so that your parkour is enjoyable to do.
I hope you take these criticisms into consideration when submitting maps in the future, good luck!