Return of Rome: Everything You Need to Know - Age of Empires
What to expect with the newest Return of Rome DLC for Age of Empires II: Definitive Edition.
www.ageofempires.com
"The Romans were intended as a bonus for you to enjoy in Singleplayer and Unranked Lobbies as an extra, on top of the content within Return of Rome. However, we’ve been listening to your feedback and desire to see Romans as a ranked civilization. Based on that feedback, we have decided to add Romans to the ranked queue in a future update."
Honestly I think this is the best solution, add them to the game give players some time to test them, balance them and let people play with them in the casual game mode that is ranked.