Hydromancerx
C2C Modder
Some more brainstorming for future cultures ...
Huastec
Req Region: American
Req Resource: Pearls (Based on Shell Artifacts)
Req Terrain: Jungle
Unit: Plumed Archer
Mixtec
Req Region: American
Req Resource: Gold (They were skilled Metal Workers)
Req Terrain: Peak
Unit: ?
Tarascan
Req Region: American
Req Resource: Tin (Source of Bronze tools and jewelry)
Req Terrain: Forest
Unit: Coyote Runner (Toltec would get a new unit)
Tlatilco
Req Region: American
Req Resource: Fine Clay (Had exotic ceramics)
Req Terrain: -
Unit: ?
Tlaxcaltec
Req Region: American
Req Resource: Resin (aka Copal which was used for ceremonies)
Req Terrain: -
Unit: Tlaxcaltec Warrior
Totonac
Req Region: American
Req Resource: Vanilla (If made into a map resource)
Req Terrain: Jungle
Unit: ?
---
Olmec
Req Resource: Cocoa (First civ to cultivate Chocolate)
Toltec
Unit: ?
Zapotec
Req Resource: Cotton (Based on Cotton Armor)
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Helpful Links
- Historical Armies Illustrated
I will update later as I get more ideas.
Huastec
Req Region: American
Req Resource: Pearls (Based on Shell Artifacts)
Req Terrain: Jungle
Unit: Plumed Archer
Mixtec
Req Region: American
Req Resource: Gold (They were skilled Metal Workers)
Req Terrain: Peak
Unit: ?
Tarascan
Req Region: American
Req Resource: Tin (Source of Bronze tools and jewelry)
Req Terrain: Forest
Unit: Coyote Runner (Toltec would get a new unit)
Tlatilco
Req Region: American
Req Resource: Fine Clay (Had exotic ceramics)
Req Terrain: -
Unit: ?
Tlaxcaltec
Req Region: American
Req Resource: Resin (aka Copal which was used for ceremonies)
Req Terrain: -
Unit: Tlaxcaltec Warrior
Totonac
Req Region: American
Req Resource: Vanilla (If made into a map resource)
Req Terrain: Jungle
Unit: ?
---
Olmec
Req Resource: Cocoa (First civ to cultivate Chocolate)
Toltec
Unit: ?
Zapotec
Req Resource: Cotton (Based on Cotton Armor)
----
Helpful Links
- Historical Armies Illustrated
I will update later as I get more ideas.

To have them so they don't clog up the other buildings and resources would be great! So far the only technique as been calling it Culture "something" since they list alphabetical. But the resources don't even have that so they are mixed up with all the other resources which can be difficult to tell what is a culture and what is a resource.
It would answer a lot of the questions you ask.