Why differentiate? Why not something more general - priority seating for ANY guest staying at the hotel that the restaurant is tied to (whether cash or DVC). Just as a course of business.
I was under the impression from the OP that it was to promote booking in your home resort. As I said earlier in the thread, I am split fence on the idea.
I think it would be a good idea to promote booking your home resort because it might help to ease some of the jam in the system. Honestly your home resort should mean more than the cost of maintenance points, when the term is up and a 3 month booking advantage. But I doubt any of these suggestions would matter. A bonus to staying in your resort wouldn't fix anything, because if your resort is busy you will still seek another hotel. What would really matter is not honey to bring you to your resort, but vinegar to prevent you from going elsewhere, and that would be bad for a number of reasons (especially since it's against our contracts!).
And I do not want vinegar to stop me from booking somewhere else since I want to (on occasion) see all the resorts. That's part of the fun of DVC.
So in the end, I guess I am missing an end goal for this conversation.