What I'm currently doing is run a few elite STFs, cashing in marks and neural parts for 500 and 1,000 dilithium, respectively. Do this a bunch of time, plus starbase 24 and the daily fleet action and I have about 20K dilithium stored up. Play whatever I want the next 2-3 days, or at least logging in to refine and move on.
Faction or Not?: As already stated ... yes/no. The Republic is a faction, but it is not as full a faction as the Klingons, whom aren't as full a faction as the Federation. There's room for additions and since STO is a MMO, that's how these games work. Having players play Rolumans but still keep those Tier 3, 4, or 5…