We can look at the pairs of Torvald+Nora and Krogstad+Mrs. Linde as a foil as well. One relationship is generated by dishonesty but solidified by brave and complete honesty. The other is destroyed by honesty.
I'm not as sure about using Dr. Rank as a foil for Torvald, but maybe you can find a good argument to make on that point.
You're absolutely on the right track with the relationships you've already named. I would also try to place Dr. Rank in there somewhere. He may even make a better foil to Torvald than Krogstad, since he is such a confidant/potential love interest for Nora.
Thanks so much. XD !