In my opinion (which is probably a minority opinion), if a group of older players has been in power a Very Long Time, and they show no evidence of active attempts to involve newer players, they're a de facto clan– passive exclusion is no better than active exclusion. This is especially the case if the only way you can "break into" their clan is by participation in some ludicrously odd behavior– like RPing your character as insanely sadistic or obsessed with chutney and tutus.
Well, hang on. I think you have to be careful, because there are multiple things going on here, and potential problems of definition.
First off, how do you determine whether a given player is on the inside or the outside of a given alleged clan? Is it only being allowed to hold positions? If so, then no clan can be very large. Is it just that they interact with the player in a non-belittling manner? I think this is particularly important to be clear on, because if you're going to label any group of characters who have been in power together in a certain realm for a while a clan, then...well, like you said, you're going to be seeing clans everywhere.
Second, I think that an important part of defining a clan
must be intent. If you've got four Council members who are all dedicated to ensuring that no one else gets their own positions, but also all hate each other and wouldn't lift a finger to prevent someone else from getting one of the other seats, that's not a clan, even if the effect is that other people are excluded from the upper echelons of the realm.
Finally, you're clearly once again talking about the specific case of Outer Tilog. I can tell you with certainty that you don't have to roleplay your character as insane at all to be able to participate. I think you'd probably agree that if there's a clan in Outer Tilog, I'm part of it (despite the fact that I currently have no character there)—and the character I kept in Outer Tilog for longest (I think; if not, it's gotta be close) wasn't insane, sadistic, or particularly disturbed at all. She was pretty frustrated, and having some identity issues, but she didn't eat human flesh, she didn't get off on hurting people (including herself), and she did think that reading and having fun were good things. The other thing she didn't do, however, was try to change Outer Tilog's nature. She didn't believe that just because all the people there were evil, she had to try and wreck everything they did, or rebel and take over, or anything like that.
So, if you want to play in Outer Tilog, then go ahead. Do it. The only restriction on your character's personality or RP is that they have to at least be able to tolerate the kind of atmosphere that you already know characterizes Outer Tilog.
Thinking you could do otherwise is like thinking you could rise to power in Riombara while being actively and vocally anti-Republic, or in Astrum while actively and openly trying to destroy Sanguis Astroism. It's just muleheaded stupidity.
