Hmmm...
Greece and Rome are too similar for two separate settlements, I think. Maybe a "Greco-Roman" style settlement.
Babylon...or an ancient Assyrian settlement, maybe. Either could be good. Sumerian, even. Kish, Lagash, Ur. Nice big temple to a Deity whose name is best not spoken as one of the rewards... (Kidding, I LOL. Maybe let's stay out of Mesopotamia. Hey, why didn't we ever have an Historical event for HP Lovecraft? That would have been GREAT.)
Persia = Iran, a Muslim nation, and not a really good idea for a "cultural settlement" in a game. These folks tend to get upset about things like that.
China...maybe if we hadn't already been inundated with Japanese cultural items, yes. We've got the Terracotta Army as a GB though...maybe they could give us a replica of the Great Wall to go with it, or even the Thousand Buddha Grottoes.
Saracens are Muslim Arabs, so again, not such a good idea.
Hard no on the colonizers from Spain. Seriously. However, if they developed a settlement based in, say, Andalusia, 15th century, that might not be too bad. One of the rewards could be a statue of Esclavo, the foundation sire of the Andalusian breed of horse. Or a settlement in Madrid. Madrid is good too. Doesn't have the horses, but...I could let that slide.
They've already got a South American Indigenous settlement on the way, and I've no faith that the development team would do right with a North American Indigenous settlement. That's just me though, I certainly don't have to do the settlement to progress through the Eras. Not like I had to do those stupid provinces on the bloody World Map. But not like that can improve.
Anyway.
They could do a great Dutch settlement, I'm sure. We could get a cobbler's house, and instead of having a second upgradable building, each time you finish the settlement, you get a 3x3 patch of tulips. You have the option of choosing the color of the tulips, of course. I would put my statue of Esclavo right in the center of the patches, and with my Sunflower Mill of Fall, my Ponds Cottage, my September Cottage, the Harvest set we just got, and my Yggdrasil all put together with it--OH MY GODS I WANT THIS NOW.
Ah, sorry...sorry. A little carried away there.
So, Troy it is, then.