Yes I know about the alliances and all, but even with that, they need to have their own Veteran and Timeships. At least. I mean, Romulan, KDF, and Federation Timecops battling it out? Now that's a temporal war!!!
Is Timeships your battle for the week? Last week it was how Roms weren't Roms and this week it's how Time and Vet ships won't work unless they're Romulan?
STO is about my Liberated Borg Federation Captain with his Breen 1st Officer, Jem'Hadar Tactical Officer, Liberated Borg Engineering Officer, Android Ops Officer, Photonic Science Officer, Gorn Science Officer, and Reman Medical Officer jumping into their Jem'Hadar Carrier and flying off to do missions for the new Romulan Empire. But for some players allowing a T5 Connie to be used breaks the canon in the game.
As for Romulan Time ships, they will probably get added the next time the developers roll out a Temporal Lockbox promotion, there should be enough demand for them. But if I'm wrong, a lockbox goody though is by no means required.
The 1K ship is a bit trickier. The point of the 1K ship is to encourage lifetime subscriptions. Sure, we can talk about 'encouraging player loyalty' and 'rewarding dedication' all we want, but the second they gave new lifers access to every veteran reward, the lifetime sub became a 300 dollar in-game benefits package with the 1K ship being the cherry on the top.
If the Romulan Faction brings in a significant number of new players, even a bump of 2 or 3 percent, then I could see a 1K ship happening. If not, then I'd say no. But take heart OP, in the Dev Blogs they described the Mogai as a "destroyer-like" ship. My hope if is that a Z-Store version of the Mogai will be available with destroyer stats and a universal LtC slot.