Fuck, I've been waiting for one of these. Been on a real kick concerning Mesoamerican civilizations lately. I'd highly recommend looking into Rise of Quetzal mod for Medieval 2. It just was released a few months back, and has a large roster on Central American city states. It's basically a much better version of the Americas expansion. Another good game I've been playing is Dawn of Mexica. It's a rougelike set in the Fifth Sun era during the Spanish invasion. The sun has gone out and you're trying to find out why. You can even perform sacrifices and kill that fuckwit Cortez.