Something I'd be curious about is how far the story will go with the Optimates and Populares when it comes to parallels with Rome.

As in, one reason Julius Caesar was assassinated by the Roman Senate was because Caesar was Populares, and his assassins were Optimates. Because Caesar wanted to consolidate his power by riding on the approval of the masses (or so his critics claimed), and the Optimate Senate wanted to keep the power in the hands of the nobility and out of the Dictatorship/Emperor. So it's not a case where the Emperor must be aligned with the nobility; in fact, quite often the monarch is directly opposed to the nobility (Louis XIV is kind of the poster boy of this when it comes to breaking the power of the nobility), and whipping up the sentiments of the middle classes and peasantry is often a useful way to keep the nobility in check.

However, we're told here that the Optimates are the hawkish faction, and Varis is also a hawkish Emperor, while the Populares are the dovish faction, and the 4.4 trailer also calls them the "liberal voices". So I'm not sure how far to read into the names of the factions here.