this is not a proper review, just some feedback
i have two sugestions,
0) maybe you want to explore other options than altered melee, just to rest a little about that type of maps, i dont know, you are good with triggers maybe you can explore the rpg or hero arena types, or something very important... terrain, start to make your own terrains, it will be interesting to see your skills making maps.
or
if you want to continue in this line of altered melee, i sugest you to dig more deep in altered melee maps, thats mean to include to your maps, this stuff
1) new custom heroes (3 or 4 per race)
2) new custom spells for heroes and units
3)if you want, custom items too
4) custom tech tree, such as updates for units and buildings
5) Probably for this you should start to use imported material
5)because the thing of aracnids and nerubians or the frozen undead, i feel the presets units limits you, imported meterial such icons,skins,models will allow you to expand your posibilities.
for example you can find proper troll workers here in the hive, with the gold and wood carry model properly
6) Also, you can play the new races,thats really good, but they need balance work so the other races wont be unfair to the new ones (an example is in the number of heroes you can use in the new races, min you need 3 heroes per race)
7) overall, im agree with Legal about imported the use of imported material, consider it a push foward to improve,but take your time, no rush, you dont need to start now.
8) the good thing is you can play with old races and new ones, i like that and you copy paste preset units, thats i think is clever to avoid unbalance.
i think i didnt say it. but altered melee is not my favorite camp of knowledge i feel more secure with normal melee
good luck