Torvald's concern with beauty, and more generally, with appearance, says a great deal about him and about the society in which the Helmers lived. Appearance was more important than reality; it was essential that he appear to be the person he was supposed to be. Nora was part of that, as was her beauty. She was his trophy.
We see some partial change in the last two to three pages of the play, but it is just that—partial—and too late. I've never believed he could sustain it, but he does make a gesture towards greater depth.