How wonderful that you are staying as a guest at the Grand Flordian concierge level - truly lovely!
Since you are planning on dining at the signature restaurants, the
deluxe dining plan is probably a good match. It includes 3 dining credits a day for each guest making it easy to plan on a fine dining restaurant each day as well as another restaurant, either table or counter service (counter service may not be the most beneficial to make the most of your dollar, however). Here is the tricky part, though. As a concierge guest, you will have access to drinks and snacks throughout the day. On the deluxe dining plan, you will receive a refillable drink mug per person and two snacks a day. I'm not sure how much you'll actually use those during your trip, especially the mugs. As for the snacks, you can use your credits to purchase snacks that travel easily and bring them home. We just did this with our trip last week and are still eating fudge from WDW!
I'd encourage you to look at the menus of the restaurants you are planning on visiting (nearly all menus for table service restaurants are available at www.waltdisneyworld.com) and have each person place a "pretend order" to see if it economically makes sense to use a dining plan as a concierge guest. Each table service order will include an appetizer, entree, dessert, and non-alcoholic drink on the deluxe plan.
Thanks for the question; if we can help again, please let us know.
PS Love your name!