that they both undergo significant changes over the course of the story, with the visit to Pemberley being a key point for both of them. My only point on its being Lizzy's change rather than Darcy's was related to Lizzy's seeing the estate itself and how it struck her:

"...and in front a stream of some natural importance was swelled into greater, but without any artificial appearance. Its banks were neither formal nor falsely adorned. Elizabeth was delighted. She had never seen a place for which nature had done more, or where natural beauty had been so little counteracted by an awkward taste..."

IIRC, this was the portion of the story that was referenced in the post I responded to.