because he was the guy that the weird shit always happened to in DS9. whenever a character had to wake up and realize they were a clone of themselves from the future programmed to kill the president or whatever, it was always O'Brien. he was the only character normal and happy enough to need those things to happen to him to keep him interesting. except possibly jake sisko.
i *really liked* New Caprica! a lot of fans were pissed about "Tent City Galactica," but it was exactly the kind of risk-taking that makes me love the show's writers. Recontextualizing all the characters into completely new situations, ones that stayed totally true to their characters and history but made us see them from weird new angles. Tigh as a resistance leader? Tyrel as a union boss? Baltar as a dictator? Yes yes awesome more please!
The return to the Battlestars was a retreat from those interesting choices, BSG De-imagined. The Cylon politics kept the show from devolving completely into muddled torrid Adama-Starbuck romance. But I don't think it ever fully recovered from failing to stick with the awesome character evolutions it toyed with in early S3.
In S4, things really seem to have "X-Files Syndrome," where the fans are taking the plot far more seriously than the writers, who have no idea what theyre going to do next and are now just kind of flailing around writing nonsense.
And the soundtrack for almost every John Carpenter movie has been sampled to death, esp The Thing and Assault On Precinct 13. Or if there are any that haven't been, they should be!