EotA. Not only do I consider it to be the best gameplay wise, it's one of the most unique and innovative AoSs ever.
-Upgradable items makes for items to be strong throughout the game (even the item you uy at the beginning).
-Stat based spells keep spells good all game long, unlike DotA where skills become outdated. In DotA items > skills. In EotA items make skills better.
-You can spend crystal on stats and skill points (they aren't imba either, unless you use crystal generators which are one of the flaws imo). Talents are another way to spend crystal, and they add effects to your skills making for more customization each game. -There are generators that can be built which can be upgraded to a whole wack of things. Energy allows you to make the generator into different things, or you can build unit towers to add to unit waves (which is pretty much necessary in multiplayer).
-All the skills in the game are unique, and very beautiful effect wise. The spells are a bit unbalanced, but the heroes themselves are pretty balanced when played properly.
-There are four areas that you can play. Each are quite well terrained although I've seen better. It is better than DotAs.
-There are three races, which could be seen as a negative or a positive. I like it personally. Only two races play at once, and it is random which race you will get. There is no all pick. In fact there is only one mode, but there are multiple ways to win.
-You can see the damage of all your spells at any time (everything calculated).
That's all I'll say for now. It's too long already.