I did some minor skimming of the other maps, and managed to make a very loose outline of the future terrain--turns out that on the left half of the map, 250 is about...50 tiles too many.
...In spite of 200 being about 50 too short on the right half of the map.
Looks like I'm going to have to improvise some terrain, then. Might need to look at an actual geography map to get an idea of what terrain I'll be improvising, specifically, because I'll be including stuff north enough to maybe be worthy of a north pole in places.
We'll have to see, exact map is still forming in my head.
While I was at it, though, I took a quick inventory of cities to make.
Many cities will, inevitably, overlap; what I ended up coming up with, though...was.
Well, Persia's still got far too few cities.
Carthage is a bit short on cities as well.
The Goths, on the other hand? Go from being one of the smallest to hands-down one of the largest powers in the game. (Oops?) Since they combine half the French, half the English, all the Vikings, the Germans, the Russians, Prussians, Austrians, Polish, and more rolled up into one.
The Celts, for their part, also expand quite a bit, to be a respectable power--not as strong as the Goths, but controlling a fair amount, as the other half of the French/English with their own holdings added in.
The Mongols (combo Scythians/Huns/generic Asian/Mongols) are pretty screwed over comparatively, as are the Persians/Carthaginians. (Carthage can only expand to include so many cities. Including the Spanish/Portuguese/Arab cities only does so much good when they all occupy the exact same territory, the Iberian Peninsula and the northern tip of Africa. Persia runs into the same problem; they only have so much land mass to expand into.)
Technically, so too are the Egyptians, but that's by design rather than anything else. (And, heck, terrain-wise Egypt isn't that terribly bad off; they've got a lot of resources nearby to work with. Gold, Horses, Iron, Spices, Gems, Ivory...)
All-around it's exhausting, but I am progressing.