If you are planning to do 1 table service per day (especially if any are buffet lunches / dinners) the DDP could be a good fit for your family.
DDP Kid's age 3-9 is $11
Kid's counter service meals are $4.00
Snacks are $2-$4
Average kid's meal entree $5-6
Without tax and tip you are at least at break even if not ahead a little.
If you do a character dinner
Buffet $12
counter service $4
Snack $2
With tax and tip you come out way ahead.