The aztec is a great civ, but they are not as good against human as against AI. They're autohealed don't work if you retreat from battle so with two armies you can destroy they're defensive unit. For the horsemen rush at the beginning they are quite good because they don't lose turn on the ennemy capital for healing. But again, against human it's not as effective. Any civ can use the horsemen tactic, but when u see one do, the best defense in the esrly game against that is to yourself buy an army of horsemen and wait for the ennemy army or go near it's last conquest.
Also, when you build an army of horsemen it cost 60 shield that are not put toward science or settler in the early game. Settler crate good city compare to a capital because you decide where you put it.
The temple science bonus is really good, but not that much. The 40 shield in the beginning of the game (where the +3 science is ss changing something) is better use building new cities that will produce at least each +2 science at the beginning and more as the game continue.
So I don't think the Aztec are overpowered at all.
Also, when you build an army of horsemen it cost 60 shield that are not put toward science or settler in the early game. Settler crate good city compare to a capital because you decide where you put it.
The temple science bonus is really good, but not that much. The 40 shield in the beginning of the game (where the +3 science is ss changing something) is better use building new cities that will produce at least each +2 science at the beginning and more as the game continue.
So I don't think the Aztec are overpowered at all.