I feel like the build feels bland and boring, and the parkour feels boring, just the same jumps over and over. I like your idea though, just felt like it could have been executed better! Good luck!
Unfortunately, I will be REJECTING this map submission.
Theme: I'm inclined to say that the map isn't very original due to our map "Clouds", which features clouds just like your map. They just aren't raining, but I don't think that slight difference is enough to merit the similarity in theme. So, in my eyes, your map's theme is not very original.
Build: Personally, I don't think the build is very good. The first issue, of course, is how similar the build is to our "Clouds" map. We don't want similar builds on our server. Besides that, your build is just really simple. A lot more could have definitely been done.
Parkour: The parkour was pretty fitting for the difficulty, although I found it to be quite boring to do due to how linear and repetitive it was. You basically used the same couple of jumps/blocks for the entirety of your parkour, proving to make it a very unenjoyable experience. Don't be afraid to venture out and incorporate a bunch of different jumps!
I hope you take these criticisms into consideration when submitting maps in the future, good luck