Hello there!
Since you ask for feedback you shall receive ;)
I will say outright that Beach/Sandy maps have become a bit of an overused theme to a point where they don't get accepted at all anymore, no matter how good the build. This build I feel would definitely fall into that category.
The leaves of the palm are a bit too long in my opinion, but otherwise the build is accurate. Generally this build falls a little flat with me though, as it is what it is. A palm, but that's not the most exciting theme of all time...the platform is very plain as well with only sand, and lacks any texture or detail. It stays true to the theme, but it isn't very interesting, to be blunt.
I will revise this when I log back in and review the parkour this evening!
EDIT: I have now looked at the parkour, and here are my thoughts! The parkour is a bit boring, and uses far too many vines. I think part of the reason why the parkour falls a bit flat is because of the build's shape. It's pretty much just a pole! There's not much else to say about it. I think that you do show signs that you can make interesting and unique parkour though. I'd love to see you make a more unique build in the future!
Please not that I am not a map judge, so I have no say whether you map gets accepted or rejected. I just like to give feedback on map submmissions to help improve the skills of those in the community! Good luck :)