I like your enthusiasm, the design of this one is quite good, I like the terraining
You are getting the idea of fair loot, there still a road to what I call perfect but I think you are going in a good track.
Some of your creeps follow a good loting system , I want to give you this list as guide for looting (is subjetive, other users may have other list)
Green creeps: level 4-6 power up level 1, level 7-9 permanent level 1, I think the permanent is a bit more than the power up. But doing it in the other side doesn´t change a thing, this defending nothing
Orange creeps level 10-13: charged up level 2 or permanent level 2, + a power up level 1, if you aim for competitive the charged up should be set manually excluding the electric magic wand. this defending nothing
Orange creep level 14-18: permanent level 3 / charged level 3 + power up level 2 (or two power up level 1) , for competitive power up level 2 manually set excluding the tome of experience. this defending markets, mercenary camps, and goblin labs
Orange creep level 19: is almost red a charged level 4 + power up level two, power up level two and maybe not excluding the tome of experience
tome of experience may do in red creeps or orange high level in less amount.
Red creep 20-21: permanent level 4 , + power up level 2
Red creep 21-25 a charged level 5 or a permanent level 5/6 + power up level 2
Red creeps are for fountains, dragon roost and market place
goldmines may be defended with orange / red creep, diferent level should mean diferent amount of gold as reward. more level of the creep more gold
The idea is to have items diversity charged and permanent from level 1 to 4, red creeps may not be used,
(to much permanent and you will have to sell the low level ones, so the charged you will use them as soon as you get them if you are agresive)
I never put a charged and a permanent both in a same camp, because can full the item bag
Another rule mine: you followed it I like that: the orange and red with anti air capacity since I like to have air units as soon as I can, if the creep doesn´t have anti air capacity, I can take it down only with an elf flyer.
So I have 2 sugestion one general and other partcular
The general: you can adjust the loot what you have a bit more
The particular the northern red creep composed of trolls and nerubian, I think a high level unit is missing, and a charged item level 5 should be loted by a strong unit, I sugest to remove the two nerubians level 3 and replace it for a stronger nerubian like the nerubian queen level 7,
or replace the trolls and put the ice troll warlord level
an item charged level 5 shouldnt be looted by a healer with only 450 hp.
For competitive gaps between trees should be avoided since small units may walk between them, thats one of the most anoying things to fix. Thats why is better to mind that and do it good from the begining.
In the last competitive melee contest, that cost points in balance.
After all what I said I decided to rate with 4/5 (resting one point only because, I am exigent with the loot) but still very nice work!