I, for one, would prefer that Romulans had their own exclusive mission list just like the other two.
It makes sense to me to have them ally with either side. This allows people to be able to get the benefits their fleets have worked so hard for without having to start from scratch. However, this should be an alliance, they are not joining either faction.
It does not makes sense to have Romulans taking Foundry missions from the Federation or KDF lists. These lists contain thousands of missions already that are written specifically with Federation and KDF players in mind, not Romulans.
I want to make Romulan missions, and I want to make them for the Romulan faction only. I do not want to have to make them for Federation or KDF and have to include all kinds of notes saying "This is a mission for Romulan characters" because I know without a doubt that there will be all kinds of players who won't read that note and will 1-star me saying "This didn't make sense for my human Starfleet captain."
In essence, alliances are fine and dandy, but it is a separate faction and some things need to be separate.
Check out the latest episode of The Foundry Roundtable at StarbaseUGC
I did note one very curious tidbit about how cross faction teaming will work. Basically the team leader can do any mission that is appropriate for his faction and whoever he is teamed with will play through the missions and get rewards too. BUT not necessarily all rewards. Some things are still faction bound.
What does it have to do with foundry? It (apparently) lets ANYONE play ANY Foundry mission as long as they're teamed with someone who could play it solo.
You choose your allegiance at level 10. After that there are only 2 factions in the game - Federation and Klingons. The Unificationist sub-mini-faction gets some exclusive missions, green ui and some ships. Orions, Gorn, Androrians and Vulkans don't get their own foundry, the Unifictionists won't get it either.
I live in an alternate universe, where j.j. abrams and cryptic never existed,
where R.S.E. is what it always should be.