I think we could have both Civ3 and Civ4 demogames, as there are thriving MTDGs for both. I would also like to remind people that this is a Civ4 area of the forum, for the record, and that we had two polls on what people wanted. I see that a few veterans have trouble with Civ4 as the chosen platform, and that they would like to revive the traditional template. I suggest that we can open for both options, with those liking the traditional ways make a great Civ3 demogame, but not blocking us that want a more different Civ4 demogame. So, the message is, Civ3 veterans are more than welcome to start a civ3 demogame with traditional ruleset, but should not hinder or impede a different civ4 demogame from taking place.
The multiteam challenge can be handled by concurrent pitboss, with 3 players (one from each team) playing 3 different teams at once concurrently at pitboss, with 10-15 turns for a turnchat, agreed on as a standard framework. No migrations should take place before Paper is invented, to maintain privacy of the different teams as well as staying in character with that people cannot emigrate to civs they never even heard about, even less live in several nations at once. The game could also be handled with turn based, a turn per day, which is perfectly possible.