Also, I'd have the Romulans already be known to the major Galactic Players (The Vulcans, Andorians, Orions, etc). They wouldn't be the "Out-of-nowhere" enemy that fanon made them out to be.
Um, this is not fanon. In "Balance of Terror," Spock seems genuinely surprised to see his father's doppelganger on a Romulan ship. And when he was recounting the Romulan War, he made it clear that the adversaries never had face-to-face contact.