Your description of how you see him being best used reads exactly like Judd at Carlton once his groins were shot and he lost that explosive, breakaway acceleration.I'm waiting to see another game, but I've had an opinion on PFD for a while similar to this but not having him in the forward line so much. I'd rather, if he had to have a main role, he stuck to stoppages and the in and under game. He is an absolute beast at winning a loose ball and moving it downfield.
A big drawback, I've noticed since he got to the Cats and it has lessened a little along with his output, was that he sucked all the oxygen out of whatever part of the field he was in. His star power/seniority/force of personality demanded the ball in situations where he probably shouldn't have gotten it. In the forward line, he would have to reign in his natural aggressiveness at the ball and play within whatever system the forwards use. If it's his turn to go, great, he's so good at pack busting attempts at marks. But he has to learn to leave the space for others more often.
I said in his first season or two, that the other guys need to be more assertive at demanding the ball. The other guys need to stand up and claim strong, responsible roles in the side. Don't be passives, be leaders in their own right. His current missed games should be giving them another chance at that. As I said above, I'm waiting for the next game or two to see how they respond to his absence.