Gran Colombia has really surprised me, didn't expect them at all. Ethiopia is obviously confirmed. Portugal is damn certain. I'm also almost sure we'll get Byzantium. Not so sure about Babylon (hey it even cannot use ziggurat), would enjoy Assyria instead of them. And regarding last two, I'm almost certain we'll get Vietnam due to fanservice and how often it it is mentioned. So the real mystery for me is only one civ. I pray to God (not even Allah) that this civ is from Islamic Maghreb, come on Firaxis, only 3 Muslim civilizations out of 50, and this was such incredible center of civilizations. Alas, my bleak heart weeps for we may get some random North American tribe instead, to heal American collective guilt once again.
At least if that happens Maghreb will be not alone in "gigantic civilization area which almost got no recognition from series". Italy will be sitting and weeping next to it, holding tightly da Vinci, Dante Alighieri, Ferrari, Marconi, Volta, Michelangelo, and lunatic revenge notebook containing written down nicknames of all those who dismiss it due to being "covered" by Rome.
I think Ireland would have been a better choice thematically for Rise & Fall than Scotland - Ireland literally entered a Golden Age as Rome collapsed. There was also the 14th century Gaelic Resurgence during the Black Death - granted that had a lot to do with the Normans (& Norse) being disproportionately affected by plague & famine due to their denser settlements. Regardless, earning points towards a golden age when your opponents (or neighbours) are down - that has great potential as a gameplay mechanic.
Looking at Scotland's golf courses - my concern is that any take on Ireland would be similarly lackluster. Even ceilí halls would be too lazy - there's a lot more to medieval Ireland than folk music. Since Irish kingship was essentially a Client State system - but the Law was entirely in the hands of a Caste of Legal Scholars. I think some trait, building or district that deals with loyalty would be a good idea.
Personally, I'd rather not have Ireland unless it was done right.
I am honestly slightly irritated than Scotland got "golf course" UI and Canada got "hockey rink" UI. So many dignified possibilities, but let's go with the lowest memes; after all those Scots and Canadians are such funny strangers!
I mean, it's not malevolent, but if America got Saloon, Aztec got Human Sacrifice Pyramid, India got Joga Center (Jesus Christ it's such terrible idea I have impressed myself!!), Japan got Anime Studio, Korea got K-Pop Studio, England got Tea Shop, Germany got Oktoberfest Pub and Russia (or Poland lol) got Vodka Factory - then I'd be really goddamn concerned.