Martok always seemed to polar opposite of Worf. Worf's all about tradition, honor and what not... while Martok just knows what -really- makes Klingons tick.
As for a favorite scene... hmm, I liked his relationship with Sirella, even if most of it was mentioned off screen. "Enough of the war with the Dominion, tell me of the war at home!" when asking Sisko how his marriage was going.