I have no idea how to make scenarios but I would LOVE to play a Cahokia scenario or a more general Mississippian Culture scenario. At its height Cahokia housed over 30,000 people and had henges, copper, palisades, and well-established agriculture at the confluence of three rivers. The creator would have to employ some artistic license with its flora and fauna and ridge-and-swale topography, but it could even be interesting to establish a timeline associated with the settlement's boom during the Medieval Warming Period and subsequent decline during the Little Ice Age. If anyone is interested in creating this scenario or even wants to help me out in learning how to make one myself, I would love to hear some ideas.