Erm, I suppose you got the whole choosing your ~father~ or your ~instincts~ thing!
But the problem is that while we got 50 episodes of Zuko struggling with his destiny and trying to make the right decision. We got maybe 14 minutes of Asami screentime over the course of the entire series so far? I like the direction the show is going in, but the emotional resonance of that scene was severely handicapped by the fact we know shit all about those two characters. That moment would have been infinitely more powerful if we knew more about Hiroshi and Asami.