I want to mention some historical innacuracies I've seen in the game. These are all in relation to religion.
First, Rome and the rest of Italy are considered Hellenistic. I'm very sure this is wrong, though Roman religion was similar to the Hellenic one, but also very different. First off a lot of gods were more warlike, including Jupiter/Zeus, Bellona/Athena, and Aphrodite/Venus, just to name a few. This was across the entire pantheon, and Mars was a lot less of a comic book villain than Ares. The warlikenes wasn't the only difference either, PLuto not only being the god of the underworld, but precious metals, gemstones, and mining. The main exceptions to this rule seem to be Hermes and Apollo, but that's because of another thing wrong with religion.
Rome very often absorbed other religions. Most notably with Greece, but this also happened with many gallic and germanic religions too. This isn't represented in game, and I believe it should be, as its a large part of how Rome grew so large and how Rome conquered new territory.
Final thing, the generalisation of "Druidic". I understand there are many different religions that can fit under this term, and that it would be too complex to document them all in the game, but still, this is so generic it groups together hugely different religions from Gaul, Britain, Northern Italy, and Illyria. Though all focus on druids as their spiritual leaders, they all worshipped vastly different pantheons, and it is a huge misnomer to label them all ast the same thing.
These are pretty vast oversights for one of the main mechanics of the game. I hope you devs can look at this and revise this, because such historical innaccuracy is unusual for you, and I know that is something you strive to put into your games.