As an FW pilot, I can confirm that FW is broken, both in terms of game mechanics and RP perspectives. That's another thread, however.
As for pirates...
I agree that there are very few options with regards to "going rogue" aside from pirates. My reasoning is that:
- As Andy said, we like to have stories and thus a good reason our character would go "rogue". Pirates have an established backstory and purpose; several of the pirate factions have a purpose of "we do it for us because we can" (I'm looking at the Angels, Serps, and to a lesser degree the Guristas). So, the framework for purpose is already there, and even better if our character has just lost their desire to care for anyone but themselves - they have ready-made factions saying the same thing.
- RP (and EVE itself) is a social environment; for the most part, we enjoy having people to play with. Because of the above factors, there will always be some RPers associating with the "pirate" factions. So, not only do we have a ready-made backstory and such, we also have a pre-prepared RP environment with friends to play in.
- The other factions out there with an "I-don't-give-a-shit-'bout-anyone-but-me" ethos - namely, the capsuleer empires - aren't exactly RP friendly. I'm not saying you can't RP as a member of a 0.0 alliance - hell, I did so myself for a while - but it's much, much harder when you don't have anyone else there to work with, or when your alliance may do things that contradict your RP (I'm thinking about those alliance leaders declaring for Sansha Kuvakei in the "I have returned, my children" IGS thread).
- RPing as a law-man of some kind can be very, very hard in EVE because - uniquely - EVE both demands you be able to take action on your words to be recognized, and offers significant incentives to NOT engage an enemy you can't win against. Moreover, protecting your own alliances' operations in an area is hard enough (again, trust me - I've tried) but protecting everyone elses' operations too can be outright impossible. Once again, EVE's requirement for demonstratable actions means that claiming you cleared an area of pirates when you in fact haven't... isn't going to be taken well.
So, all in all, players get funneled toward factions which have an existing RPer population because we're lazy and don't like the risk of striking out on our own to pour hours and hours into something which may not work in the end anyhow. I'd like to note, however, that this does NOT mean that people's IC reasons for "going pirate" are wrong. In fact, the reasoning I've layed out above could work just as well IC - pirates are there, they have capsuleers your character may know and be friends with already, and unlike the highly unstable 0.0 alliances, they seem to be composed of people who for the most part understand cooperation.