We used the deluxe dining plan last Dec for 10 nights ... We like signature dining for dinner, which requires 2 credits. However...10 nights of Signature dining is waaaaayyyy too much! Most days we ended up bringing our desserts back to our room ...and at the end of our trip we tossed everything out of the fridge as we were never hungry again after dinner.
We went on a shopping spree just before we left to use up all of our snack credits - we came home with a bag full of nuts and other things that travel well.
I maintained a spread sheet during our trip to see if we were really coming out ahead with the dining plan after adding tip, drinks etc .. we did come out ahead, but truthfully not by much ... around 15% savings. That said, if we were going paying OOP for signature dining we would never order app/dinner/dessert .. it'sjust too much food!
I too hate the mad scramble to book dining reservations .. and trying to figure out where we might be and what we might like to eat that day 6 months in advance is so frustrating ... why or why do we need to do that so far in advance? But...if we don't we find outselves shut out from getting any dining reservations while we are at Disney.
Have a great trip!