Mostly it's about characters for me, too - but not always. For instance, I was pretty much addicted to BSG and raced through it at inhuman speed, while to be honest I didn't have much sympathy for most of the characters. There were a few I liked, but no real favorites either. Same goes for shows like Lost and Carnivale, where I liked the plot, the mystery and the tension more than any character. (Though with Lost that's changed a bit over the seasons, and some characters have become favorites.) But it's probably not a coincidence that I never went looking for fic in any of those fandoms - for that I do need a character to connect to.

Having a favorite pairing can definitely help me enjoy a show more *mumbleB5mumble*, but it's not essential. For fanfic it depends. There are shows which are almost pure gen to me (ST: TOS, for one :) ) and where I prefer to stay away from shippy fic unless it's very platonic or very well-written, and in some others I go looking for the shippy fic first. No logic in there, I'm afraid. *g*