Um, I am for the geographical regional culture areas for categorization.
The argument about colonization usually starts with limited information. The Aztecs were exaggerated by the Spanish to make it proper for them to convert them. Especially since the Spanish inquisition was going on. Anyway Maya held off against the Spanish much longer than the Aztecs....anyway a lot of stuff that I think is missing in the discussion that usually gets pasted over.
And many tribes had slaves. There was different treatment of slaves in tribes of course. Pacific Northwest had slaves. For example Chief Seattle had slaves. Thunderbird I assume you know the Mormon moundbuilder story as well by Joseph. I am not here to tell anyone their religion is wrong or their beliefs wrong because there is no real truth. But when you actually see what is made by the people you can usually find a link if their is a heavy influence. Nothing is found. The Aztec finding a bird on a cactus eating a snake is strange though, and of course was probably made up after the fact.
In fact to show an example the Maya held of the Spanish longer and an in Lamanai for example burnt a church in revolt, and left a crocodile statue (name of the city means underwater crocodile). Anyway that is how welcoming they were to the new religion at the time.
http://www.gsvdl.net/archeology/lamanai/church.shtml
Anyway the story Quetzalcoatl being white has got out of hand as well. It is guessed to start with the Toltec. And White represents..North in Mayan Glyphs (Black-East, Red-West, Yellow-South, Green Center). It assumed from accounts some Hippie from the Toltecs preaching peace not sacrifice man was exiled, and his return was how the story got twisted. Anyway I was about to give a rant about all of the people who willingly falsify the facts, but there is no point of doing this. Wal-mart stores on top of these areas just to show you how important it is to those in power.
"No, the Conquistadors Are Not Back. It's Just Wal-Mart"
http://www.nytimes.com/2004/09/28/international/americas/28mexico.html?_r=0
The Tarascans are important civilization for example that held the Aztecs back. The Aztecs never broke through. They actually had metallurgy. (Tech from northwest South America)
http://en.wikipedia.org/wiki/Tarascan_state
This is an axe found below.
Debates are now why did they not kick the Aztecs butt. It seems Obsidian was durable enough and lack of large deposits of mineral resources never pushed them on that front.
Possible draft animal differences...Maize (corn) you do not need to till the grown deep so less need of draft animals. One of the original reasons for the ox was for fields in the old world for example, and the horse came after the idea of animals to do field work.
Btw oh the dog was commonly eaten in region. The Chihuahua dog could be consider like a chicken food resource.
Anyway there is ton of info. I would rather talk about how to put this into the game versus speculation.
These below are not anything that I am locking on stone. Just some method to guide myself to diversify the areas so as to better represent the regions. Anyway if how I am looking is wrong tell me to stop.
West NA
--------West Arctic and Subarctic
--------Pacific NW, Plateau. Northwest Plains Area
--------California, SW, Basin
East NA
--------East Arctic and Subarctic
--------Northeast and Northeast Plains Area
--------Southeast and Southeast Plains Area
Mesoamerica
--------West Mesoamerican (Tarascan for example)
--------Central Mesoamerica (Teotihuacan...Aztecs..Toltec
--------East (Mayan states...Olmec)
So anyway I want to have for the Americas 4 homeland cultures...West NA, East NA, Meso, South America....with that I would like to actually see the stuff like religions as full as the middle east for example. I am wanting to equalize the beginning a little more. After that there is plenty of unique combinations that can be created from dynamic civs.
That means it is more important for me to balance regional cultures than anything else. If there was a idea of some genetic or linguistic spread than we should include cultures that were not part of the dominant Kurgan hypothesis. For example Old Europe before the migration of the Indo-Europeans into Europe. Culture does not have a direct correlation to language, but of course you can see words from the past...this could be borrowed words from other languages..and etc. There is plenty of cases where the two do not coincide. Genetics has nothing at all do with culture unless we are talking about common genetic deficiencies perhaps and dietary patterns to fix common things being part of a culture. For example lactose intolerance.