Hello magoas,
Unfortunately, I will be
Rejecting your map.
The theme is fairly original, there are a few maps that are based around planets, galaxies etc. But nothing exactly like this. The build is good, it's simple, but has some nice detail. I would suggest trying to make your main build a bit bigger though, as it does look quite small and doesn't have much room for the parkour to go into it.
The parkour is quite repetitive. You did have some variety, however you did group your jumps a lot. What I mean by this, is that you would have a sequence of just normal blocks, then just ladders etc. Try to mix up your jumps a bit more, and try to experiment with a larger variety of blocks and items, to create more original and enjoyable jumps.
Most of the parkour is floating. Having an excessive number of jumps floating around the build and the void can make your map look a bit messy, so I'd suggest trying to make your build a bit bigger, and implement the jumps into the build more.
The difficulty is good for a medium/hard map, and the length is good for an expert map. Please read over the requirements here -
https://manacube.com/threads/must-read-map-submission-information-format.649/ to make sure your map fits within the guidelines.
Thanks for submitting your map! I hope to see more maps from you in the future.