My understanding is Cady had wanted the character to become darker and more complex, a la Rosanna, which I agree gave her the best work of her career in her first stint at ATWT. So a major part of the more cosmopolitan, noir femme fatale Dixie I think was her. And tbh I liked a lot of the superficial aspects of it; her clothes, her hair, etc. I thought she had some chemistry with Thorsten Kaye though she was walking into a buzzsaw with the audience there, too. So some of the fault lies with Cady, perhaps. But I can't blame her for wanting to innovate the character to a point, as she did when she'd pushed for the pairing with David in the late '90s/early 2000s. And she wasn't responsible for the actual bad story - they didn't need to run her down as badly as they did, and that's because McTavish made it personal. You could've done new things with Dixie without totally botching that.
The story did not make much sense, but I didn't care. I think Agnes had a light hand in it, or so I believe we were told. I think the choice of making David Rasche's villain a Gardner relative screamed her. The fact that they remembered the Remy character also impressed me. Beyond that, no, it was very silly. But compared to some of the [!@#$%^&*] since it's practically 90s level.