Turn 25...
I've been sloppy with production micro, so the warrior arrives a turn late. But I'll switch to a settler right after that.
There are three natural points to start pushing out settlers. One is to grow the capital to the happy cap. Initial worker(s) improve tiles locally, then move off with the new Settler to establish the next base camp.
The second is to start training the settler at size 4, which opens up a 2 pop whip (assuming you revolt into slavery early enough).
The third alternative is to start training settlers when you run out of good tiles. The math here is that growing onto a "normal" tile doesn't typically reduce the time it takes to train a settler. This is essentially a consequence of the law of diminishing returns -- corn plus cows plus the city tile plus one hammer of overflow is enough production for a 9 turn settler. Adding another mine gives you a 8 turn settler - but the training starts 3-4 turns later.
Add a second mine, and your still looking at a 7 turn settler, having waited an additional 3-4 turns to grow.
None of these are wrong in a general sense; but there are trade offs. In a cramped setting with a good site in the contested region, I'm happy to trade some short term production capacity to get the location I want.
Yellow square is not, in my mind, that good a property in isolation -- I'm looking at it's forward position as the starting point for my war against the Mongols. A second minor food tile in the cross would certainly do it.
Additionally, the main theme of my plan is LAND, so I should go claim some.
In a more open position, I might grow more, on the grounds that I need to sink more early hammers into fog busting.
If the plan were RUSH, I would likely be looking at hurrying a settler to Blue Square to hook up the horses, so that I might most quickly deliver a stack of 10 or so chariots to the mongol doorstep. My belief is that the right play in that instance is to hurry the settler out -- but there are plenty of folks around who better understand how rush calculations work out in practice.
Red Square, despite the relatively crappy desert conditions, turns out to be a useful location. It would be my first settling choice in an uncramped peaceful game; but it's somewhat slow to develop (resource(s) in the second ring, improving flood plains takes extra time. Since I'm not worried about being beaten to that location, I'm willing to postpone it one settler.
I'm also looking at putting Gems+Cows on that plains hill to the south. It kind of sucks taking a good tile away from the capital permanently, but gems are probably worth it. There's no hurry here, as I can't improve the gems until iron working.
So the immediate priority for the next turn set is to get Yellow Square connected. Since I start with the Wheel, it should be connected as well. I'll want to get the culture going, so Mysticism is going to be important there.
