I'm going to state my opinion on the dragons, the only creeps I don't like.
I know that they(understandably) don't have a role in WC3, and that I shouldn't care, but I do.
Why? Because they have such a big role in WoW, a major plot in pretty much every expansion, and a main plot in quite a few books.
Only thing I like is how cute a bronze whelp is. The large level 10 dragon, that can take on an army, uses animations of a Faerie Dragon, which is just lame.
I like that red Dragons look kinda friendly, but all the others too, that makes no story sense.
The black especially, they should all be evil. Even the whelp should look evil (Malurion says that in RoC campaign).
The Dragon Roosts also look quite bad.
A Red Dragon is sitting on a lava. Shouldn't she sit on grass, flowers, red trees and other friendly stuff?
The black is just sitting on some black stone, it should sit on a lava, in fact red roost would fit the black perfectly.
The other roosts are also strange in story sense.
It's good that a green is sitting on some vegetation, but it should look more dreamy.
The bronze on sand, which is fine I guess, but there should also be some time related stuff.
The blue on ice, but there should be some magic stuff too. In fact the blue dragonflight should look far more magical. Same things for pretty much all others.
They should all look more scary, with the exception of the red, especially the black. The Black Aspect, thought to be dead during WC3, being one of the big evils of the world.
I do like everything about the Nether Dragons though.