Thanks for posting those screenshots. There's a potential problem with balance due to civ placement on the map. Most prominently the whole of Western North America is open territory. As is Australia - along with the many islands between it and Siam. Early expansion by Iriquois or Cahokia would give them an unfair - and perhaps insurmountable - advantage. Same goes for Siam once it has naval technologies. These areas are problems because there is no potential opponent on the other side of the territory. Look at the situation in Sub-Saharan Africa. As Mali expands South and East it will be opposed by Zulu. But Zulu has no similar problem with the resource-rich territory to its South. There may be similar cases elsewhere, but without a global screenshot I can't tell.
I think it will be balanced though, since I'm making it generally harder for civilisations to churn out settlers early, with historically serious globally-contending civilisations getting an edge for a short time during their historical golden age, or else when historically they were actually doing a lot of settling. I factor in each civilisation's greatest extent, when they reached their greatest extent, how much of their greatest extent was based on settling vs conquest, and the preservation of the opportunity for any civilisation to go beyond the bounds of their historical limits. Here's what I mean:
When the game starts out, it is very difficult for any civilisation to make new cities. Period. Not impossible, but definitely very hard and expensive. I think 3-4+ cities is plenty enough to have a decent research/tax/production base for the ancient times, especially if nearly all of one's rivals are under a similar handicap. As the ancient ages progress, though, it'll first become slightly easier for the Egyptians, Persians, and Greeks to churn out settlers, assuming they've been keeping up with their research. Then the Carthaginians will gain a similar edge for a while. Then finally in the Mediterranean, the Romans will begin dominating as the Persian/Greek/Carthaginians' settling edge wanes. And as the ancient times come to a close, the Chinese will experience their Three Kingdoms period, and begin to settle more easily across Asia. Similarly, Korea will found Goguryeo, and gain its own settling advantage.
Then the Middle Ages arrive on the scene, and the Byzantines start out with their edge. The Huns will have some sort of edge too, though I'm not completely certain on how I'll shape it at this point. They didn't, after all, exactly settle. :b Whatever I do for the Huns though I'll do for the Mongols later as well. :b By this time, the ancient settling advantages have reversed, as those nations didn't do a whole lot of expansion during the Middle Ages. The advantage instead heads in the direction of Northern Europe and Great Britain. China, China, and Korea keep their slight advantage over the rest of Asia, but seeing as how they consist of most of Asia and are rivals right next to one another, this is kind of a moot point.
Keep in mind though, that while this is going on, it is still rather costly for any civilisation to do a whole lot of settling. Also for each civilisation, there are incentives to expand in the general direction that they did expand towards historically. For instance, for the Koreans in the Goguryeo era, they need to settle certain locations in Manchuria in order to be able to build the Goguryeo special unit Gaemamusa (which is a powerful heavy knight).
Things start getting interesting in the Age of Discovery, and Iberia, Britain, and France will have a lot of incentive to colonise their respective spheres in the Americas, though their colonial territories will likely be small for some time. As the Age of Discovery gives way to the Industrial Era and the Age of Imperialism, Northern Europe, Britain, Russia, and the United States will find themselves suddenly able to go through a colonisation boom, with incentives to settle in their historical spheres. At some point, Britain, USA, and Russia will dominate the colonisation scene for a short time. And then in the modern era (circa WWII), things equalise and how each civilisation fares from that point forward will generally be based purely on which choices they make.
In addition to the colonising disparity, certain areas of the globe will see deterrents to colonisation efforts until a certain time period. For instance, in order for Rome to settle Northern Italy, they'll need to fight a simulation of the Etruscan Wars. In order for Japan to grow significantly, it'll need to fight through its Sengogku Era. Koreans deal with the Khitans. England deals with William Wallace. France with Burgundy. Germany with Bavaria. North America is home to many native peoples. And woe to any civilisation thinking of attacking little Switzerland before the Information Age ends.
Is this setup unfair? Oh most definitely, and that's kind of the point. It's meant to simulate the fact that the tides of history weren't decided by the rulers, but by various other factors that all played a part in how civilisations rose and fell. A good ruler with a weak civilisation can help the civilisation realise greatness, but can also fail all too easily. A strong civilisation with a bad ruler similarly can fall, though perhaps not quite as easily (unless the ruler is REALLY bad).
The rules are mostly designed to keep the AI in check, but they can also serve as a handicap for players wanting to test their skills. Playing as a historically powerful nation like Rome or Britain is easy, though it's not easy to go significantly beyond their historical bounds. Playing a historically weak nation like the Zulu or Korea is incredibly difficult, but a skilled player using a "weak" nation can in fact dominate the globe.
In this way, hopefully every new playthrough will become a rewarding experience.
