I can’t swallow the ad man lifestyle interpretation altogether. She was daddy’s little girl and daddy hated Don and raised her to expect more. I think he was being literal when he called her a princess, as if she could’ve been Grace Kelly. That is a character I’d like to see. One who is perhaps Don’s equal, only in a different direction. I enjoy much less the spoiled little girl who lashes out at pets for her poor marriage choice.
But even that whole princess and daddy’s little girl complex is a part of the ad man construct.
Don’s first wife was really his equal. Of course he didn’t marry her. Megan is kind of his equal, she’s at least willing to try. I’ve always found it interesting that the first wife he chose as part of his fake identity was blonde while all of his mistresses (who in many ways get to know Dick Whitman more than Don) are brunettes.