All right, the concept of the idea is pretty, but the execution is very problematic, not only due to the presence of leaks, but also because of some incongruent item drops and creep camps. So let's get started:
Terrain
This part needs more love! Over 50% of the map is pure emptiness... a flat deserted barren land of immense space. To start off, your terrain should never be flat, as no natural landscape is completely so. Creating some bumps and lowerings would be really cool and adequate. In addition, you could add cliffs, cactuses, rock spires, craters, fissures etc... all the barren doodads you can think of! Just don't leave your terrain empty! Take inspiration from other barren terrains if required. Furthermore, never spam one tile over large areas as this looks pretty monotonous and unattractive.
Some A lot of variation is needed when you create a terrain to please the eye, as we usually see in godlike sceneries of terraining contests, thus I urge you to mix the tiles more often.
Creep Camps and Item Drops
Here are where most problems rise. After examining this category, I drew the conclusion that you really need to overhaul everything here. Firstly, the creep camps. They are far too overpowered. A summed level superior to 30 is just too much. Also you do not have to put a too great number of creeps, even if they're weak (centaurs camp for example). in one creep camp Keep the number within a reasonable range of 2-6, considering also the fact that there are some powerful phoenixes roaming by occasionally. Now item drops. To my surprise, the bronze dragons have an item set which has a 100% chance of dropping... nothing XD What's the purpose of it then? What's worse is that the rest of the dragons drop nothing, which in turn means that these entire creep camps give no rewards. Additionally, the item drops are often too weak or not sufficient. Since your creep camps are numerous, it's impossible to let only one creep drop an item, for how powerful it can be. Multiple creeps should drop items of sensible levels. Take the central camp of harpies as an example. The summed level is 43, but merely one item of level 6 is dropped. This isn't fair at all!
Bugs and Leaks
I analysed your triggers and I found some leaks and errors.
Let's take
Untitled Trigger 003,
Untitled Trigger 003 Copy and
Untitled Trigger 003 Copy 2. All these three triggers could be merged into a single one. How? Just put the events of each trigger in the event of one trigger only. The action will not change. The main problem here is that there isn't the indispensable condition! Your current trigger would implicate something rather negative. If any flying unit reaches regions 003, 004 and 005, it'd be removed! Pitiful, isn't it? But that's an easy fix, my friend

Just put this condition:
-
((Unit-type of (Triggering unit)) Equal to Lesser Pheonix) or ((Unit-type of (Triggering unit)) Equal to Big Pheonix)
That will force the trigger to work only for the phoenixes.
However, my main concern is about the leaks. One trigger precisely leaks periodically, and that is
phoenix flight. The other triggers leak as well, but I'm most worried about this one. Every second, it creates leaks, and that could affect late game. Take a look at
this tutorial to learn how to fix them. It's very simple, don't worry
Based on my review, I will set this map to needs fix until it is updated. Good luck with that! And remember: never lose motivation!