My own observations:

• Graphics seem to be more stable
• Money seems to be easier to make? I'm playing on veteran mode sans Caeso + Nefu, as usual, and usually its a slog to get up to +1000 before leaving Latium; but I've been able to take out two loans simultaneously and still keep a healthy balance
• Listing obsidian as a fertility when it's present on all islands seems like a mistake. I did a double take because suddenly every island seemed to have far more resources than it usually does on veteran difficulty

::: spoiler Also, diplomacy seems a bit updated

• Athr and Concordia have threatened me with war which i think comes down to having settled Cinis early on
• Tarragon and the Vestal Concordia went to war after he settled a second Latium island, lol.
• Emperor Calidus has given me easier quests
• Calidus gives +2 rep when you level up prestige, and +2 for little events like boosting neptune/ mars worship and boosting roman population in albion. These used to be a one-off per island but gjve you 5 rep.
• since calidus gives rep for boosting prestige, some of the choice screens no longer give an immediate reputation change; e.g "A roman girl is being married off to a senator but loves someone else", the change in prestige is supposed to be enough to induce a response from calidus (it didn't for me, weirdly enough) :::

::: spoiler Some other changes to Computer-Player behaviour:

• I think Concordia's line about "loitering perverts" was changed for some reason?? Funny if so. Kind of like they wanted the game to be more kid friendly.
• Athr is more explicitly a counter-establishment character. I completely forgot this in between playing the campaign and the first DLC, but you'll notice he usually has the worst Reputation with the emperor after Nefunerru. He also gets angry at you for having high prestige. :::