I love O'Brien -- he's one of the only regular Trek characters to get married and stay married, have children, etc. I thought he was a strong character, and had many good episodes on both Next Generation and DS9. And yeah, I think he should have been promoted, but in reality--the crews of EVERY Trek series are awfully top-heavy with officers.
My son's name is Miles Benjamin--and although he's NOT named after O'Brien and Sisko, when I realized that his names were both names of DS9 characters, I thought it was kinda funny. If my wife ever finds out, I'm toast. We just liked the names--liked Miles because it was different, but not freaky--and Benjamin after the biblical Benjamin.
Of course our second choice was Chewbacca The Edge...NOT named after the Wookiee and U2's guitarist.
Right.
Back to O'Brien--I like him.
And it was nice to have someone "down to earth" like he was. I also enjoyed the friendship he built with Julian--when they started out not liking each other AT ALL. I've developed several friendships that way, and it seemed very genuine to me. Something that grew out of the characters, not out of left field.
That's it.
Quinnnnnnnnnnnnn