I'm not sure why there is such a rush to settle interior city sites, especially sites, like the western one, that don't really have much going for them. I say settle south now, and if anything look to move further south to claim more territory from the Horde (unless we've been locked in from some treaty. Something on a hill that we can defend well against their eventual next invasion.
The northern spot looks ok, but I don't quite see what the rush is. Maybe after currency, or maybe later than that.
The western spot... I really don't see the point in settling there under any circumstance. I also don't favor settling on that little 1-2 tile island.
For the southern city spot, I favor the blue spot. I think we can definitely compete for that corn.