Respectfully, opinions vary.
To me, it would have worked if they didn't have Dean do nothing until Sam got there. I've never been big into the interdependence stuff but this just soured me as it implied that Dean couldn't do anything, even in Heaven, without Sam. I know that's BS but that's how they wanted to end it. With backwards growth for Dean because even in the pilot, he'd been able to hunt without Sam.
Of course this is my view and opinion. As I stated in the beginning, I respect that you feel differently.