Just so you know, OP (I couldn't tell from your post if you know this or not), your Quick Service plan will give you all you need to eat and more, it's just that you can't use credits at a sit-down place. If you are thinking it would be nice to HAVE a couple sit-down meals while you are there, you'll just pay for those out of pocket. Sorry if I'm stating the obvious, but you had said "you know you will need more meals" or something like that in your original post.
I would suggest a character meal if you can get it. We like the Crystal Palace at the MK (with Pooh, Piglet, Eeyore, and Tigger, tasty buffet food), and since we're going the same week you are, I have seen a lot of availability there as I've tweaked my reservations online.
Best of luck, and don't pull your hair out!