I have completed (almost) size #1 of a new series, but havent yet decided on its use.

My two main choices would be:

1) steppe tribe- turkic/mongolic civ
2) central african civ

In size #2 there will already be some bigger building which will make the culture obvious, which is why now is the time for choosing ;)

If it is going to be a steppe civ i am thinking that the metropolis could be a rather small size town, like this in the pic. Also the pic helps you see how the buildings in size #1 can fit a steppe civ

it would be nice to have yurts in a Mongolian/hunnic city. Maybe ancient era could be that?

What are yurts?

I altered the first city a bit, this is it being used for a seljuk civ

Yurts are the round felt homes used by the nomadic mongols. They are not domed, but have a slight cone shaped roof with vertical sides of such height as to allow a person to stand erect inside.

Well, those houses look too permanent to be Mongolian (and other steppe tribes), so I'd have to say late-era turks (i e after they invaded and settled Anatolia) or Africa.

yurts are like tent home, because peoples from mongolia and central asia were often nomatic
http://danny.oz.au/travel/1999/pakistan/p/p/807-yurt.jpg
http://www.inventory.mcmail.com/hiroshima/images/yurt.jpg

Ty for the info & pic of the yurts, i made a new size #2 with a yurt-type building as well & changed the colours. What do you think, does it look mongol now or not?

well ancient should be all yurts.

Im not sure that i will be making more era's of them. These are supposed to be medieval. Although perhaps i will make an ancient one as well, but not industrial/modern

I think there was a ceremonial yurt-like structure in RedAlert's single-era Mongolian cities. You could probably use that. :)

It is too generic, + actually i used it as a base for my own red yurt ;)

This is size #2.
Do you think that a mongol metropolis should be of the regular metropolis size, or considerably smaller?

@Ogedei: i think that your tibetan series had a rather small metropolis