I think there's a clear-cut difference between being unable to say a character is possible / can act a certain way, and being clearly able to tell that the character in question breaks lore hard. If you wanted to play something outrageous like one Ni-Kunni twin who was separated at birth from his/her other Ni-Kunni twin who was raised by Gallente/Minmatar parents while the other was raised by blah blah blah child actor, movie star, stupid things like that? Fine, fine. If you can make it work, not overdo it, things of that nature, I'd actually like to interact with someone as outrageous as that.
It's already been said, and I don't like just bandwagoning, but I agree with the idea that some stuff is just... too wrong. EVE Gate travel, Earth? Let's not. Super mind-melting hyper lasers out of my eyes? Nah.
Creating new content as V said is important to furthering new plots of RP and to keep things moving on along. When someone or something just sits there, nothing interesting or found out, we get the Summit-fests where everyone's just fiddling around and asking about the weather, then suddenly it's all about slaying Gallenteans.