I found the following places to be good value with slightly larger portions.
DTD-Wolfgang Puck Express Marketplace.Wow,this is fantastic value for a qs credit and lots of food.Highly recommend the meatballs,meatloaf+rosemary/garlic chicken+mash.Plus crème brulee cheesecake for dessert.You also get refillable drinks here.
AK-Flametree BBQ-You can get a chicken+ribs combo with a pot of coleslaw and a pot of bbq beans.(plus dessert+drink).
AK-Yak&Yeti-Food is served in the Chinese takeaway cartons.I recommend the beef lo mein and sweet+sour chicken with rice-ask for some plates to empty your food out onto if you have the chicken otherwise it's really hard to get to the rice underneath.We have a 13 and 9 year old and because its a lot of food we tend to share 3 qs credits.(plus dessert+drink).
MK-Cosmic Rays after 4pm(I think) you can get a chicken+ribs combo with mash potatoes and green beans(plus dessert+drink).There is also a fixin's bar,so you can fill up on mushrooms,onions,salad,hot cheese+pickles.
MK-Pecos Bill does a big 1/3lb deluxe cheeseburger with bacon,onion rings+bbq sauce,comes with fries and they also have a fixin's bar.(plus dessert+drink).
DHS-I tend to struggle with a good counter service here,but I would go for Starin Rolls,with large freshly made sandwiches on foccacia bread,ham or turkey,bag of chips or fruit,plus a cake+drink.The cakes here are amazing and large.
Epcot-Sunshine Seasons,i recommend the pork chop with bbq sauce and mash potatoes(plus dessert-which are also lovely here+drink which are refillable).
Epcot-Lotus Blossom Café-lovely Asian/Chinese food,i recommend Orange chicken+rice or Shrimp fried rice with egg roll,(plus dessert-ice cream+drink).
Hope that's helped you a little.x.