"Mr. Darcy was punctual in his return, and, as Lydia informed you, attended the wedding. He dined with us the next day, and was to leave town again on Wednesday or Thursday. Will you be very angry with me, my Dear Lizzy, if I take this opportunity of saying (what I was never bold enough to say before) how much I like him? His behaviour to us has, in every respect, been as pleasing as when we were in Derbyshire. His understanding and opinions all please me; he wants nothing but a little more liveliness, and that, if he marry prudently, his wife may teach him. I thought him very sly; -- he hardly ever mentioned your name. But slyness seems the fashion. (Chapter 52)

In the bolded sentence above I think Aunt Gardiner is describing how she sees Darcy, “his understanding and opinions all please me” and when she says “he wants nothing but a little more liveliness” IMO she is still giving her observation of his character. I read it as meaning Aunt Gardiner believes if Darcy was a little livelier then he would be pretty near perfect. I do not think he voiced a desire to be livelier. She even goes on to say the right choice of wife (meaning Lizzy) would give him just that.

I have thought that Darcy learns to think beyond the list of accomplishments he and Caroline establish in Chapter 8; that perhaps the list was limited in depth when judging the worth of a lady and he comes to realize that. You have an interesting idea. I have never actually compared Darcy’s feelings on accomplished women in Chapter 8 and his feelings later in the novel. Could you explain the similarities you see; what characteristics or accomplishments he described then to what he sees and likes in Lizzy now? ;D