This leaves aside the Rihannsuverse, possibly novelverse character of Ael, who as Empress may have triggered a fairly intimate rapprochement with the Federation. It takes something pretty significant to explain how Nanclus was able to sit in on a classified Federation briefing to the UFP president how Starfleet would raid the Klingon homeworld if the RSE wasn't pretty impressively friendly.
One of the stronger arguments for incorporating Ael, and Rihannsu's
basic story, into the mainstream novel continuity is certainly the fact that between around 2275 and 2310 (loosely) the RSE seemed to pursue genuine hopes for a good relationship, even an alliance, with the UFP. Ael and the civil war would help explain that (we have D'tran and his supporters prior to this in Vanguard,
of course,but full government support for peace would come significantly easier if Rihannsu
is "counted"). Then Vokar and his ideological cousins rose up, unfortunately, there was Tomed
...and the borders closed.
Extrapolating wildly, if the IRS does hold the northeastern half of Romulan space, that ]might indicate that it holds more the colonial frontier. Judging by the Rihannsu novels, which suggest that the colonials are more liberal and humane in the idealized Romulan sense than the homeworld might like, descended from the Ship Clans which were never that invested in the myths brought by the colonists, well. Thoughts?
That's an interesting idea, and I really like the suggestion. It would be great to have a sense of the rate and direction of Romulan expansion, who settled where and when and where the strongholds of each ideological perspective or sub-culture are. We can dream...