Well, working with other factions (especially factions your "parent" faction doesn't get along with so well) tends to result in Controversy. That's not to say that it's a bad idea, necessarily, but it does result in people going "Grrr" and "Argh" at you on the forums and trying to undercut your credibility.
Gathering roleplayers before you declare loyalty to a particular faction has a way of causing half your team to jump ship, unless you're a truly first-rate consensus-builder. People whose characters
care about things will tend to gravitate to a cause (and characters oriented towards RP tend to have things they care about); you get a lot of flexibility with people whose primary goal is to blow stuff up, but perhaps rather less loyalty and people like that seem to get impatient if roleplay starts "getting in the way."
Personally, I'd suggest starting small, being open about your allegiances, going for serious roleplayers, and trying to
corrupt any "empire" roleplayers who happen to strike your fancy.
sourceYou don't have to wait for Angel roleplayers to start spontaneously appearing out of the woodwork when you can
create them. Most Eve players who don't have an active moral horror of piracy are susceptible to the above.
*I* certainly was.