Unfortunately, I will be REJECTING this map submission.
Theme: The way I see it, this map is themed after ore's as they're what the build is mostly comprised of. Which, is not an acceptable theme as it's completely unoriginal and uninspired. This also applies to any other map that is themed after Minecraft blocks.
Build: Personally, I don't think the build is very good. It's very unappealing to the eyes as it's just floating ores all over the place. It lacks organization and attractiveness. In the future, I recommend that you first pick out a proper theme, portray it in a much more orderly manner than this, and integrate your parkour into it (not have it floating all over the place).
Parkour: The parkour was definitely hard enough to be a medium, but it was way way too long. It reached about 110~ jumps. You have to remember that each difficulty has a jump range and, in this case, you were to make a parkour that was 40-60 jumps as it is a medium difficulty map. Then, there were issues with the parkour's variation. You would put the same jump and block back to back too many times. For example, the core ore segment, the gold ore segment, and the ending ladder segment. All of these segments are comprised of the same block and jump (for the most part), proving to be very boring. You have to be more creative!
I hope you take these criticisms into consideration if you decide to resubmit your map in the future!