I don't think I will. The Valley of Mexico is just too small for that.
Isn't that why we have city-states though? Italy, and maybe Carthage and Greece are really the only prime contenders for city-states usage when going for the UHV's. Given a few small adjustments, the Aztecs could have a fairly unique playstyle. Right now they're not all that interesting, and even the new goals don't seem to set them apart.