I think the only time the dining plans are a "deal" is when they are free. Otherwise, you are more than likely paying more than you would if you were buying your meals. IF you drink soda and eat dessert at every meal, you might break even, but here are some things that DD and I have discovered:
>Even though we are walking around all day, we aren't as hungry at Disney as we are at home. I think it's the heat- we just don't eat as much at each sitting.
>We have snacks at Disney (that we normally wouldn't have at home) and prefer these to the sometimes-dreadful desserts that are included in the dining plan. Usually after a meal, we don't want dessert but it's included in the DP, and if we do eat the dessert, then we aren't hungry for the snack (or don't want the extra calories). Yes, the dining plan includes a snack, but if you throw away or skip the DP dessert, then you are wasting money.
>Many of the QS meals are big enough to share. Flame Tree BBQ has a chicken dinner that is HALF a chicken with beans, cole slaw, and corn bread for $10.49. DD and I share that for lunch or get an additional side of beans and call it supper. Cosmic Ray's has a half-rotisserie chicken with mashed potatoes and veggies for $9.99.
>Even if you don't share meals, if your DD really is a selective eater with a small appetite, she can choose a kid's meal. These are smaller portions- but not necessarily just chicken nuggets or a burger- with smaller prices. Yes, on the QSDP she could also choose a kid's meal, but you would still be paying for an adult meal plan.
If you are really worried, run the numbers yourself. For us, a normal day's meals would look like this:
Breakfast at POP: 2 kid's breakfasts ($4.99x2) OR a bounty platter ($9) and fruit cup ($3.50) to share.
Lunch at Flame Tree BBQ: Chicken BBQ platter ($10.50) and a side of beans ($2.39). We don't drink soda, but DD might have an iced tea ($2.69).
Snack: Mickey Bar and a frozen banana ($9? Don't recall actual price)
Dinner: Since we have park hoppers, let's say we hop to Epcot for the evening and have dinner at Tangierine Cafe. I'd have the lamb schwarma platter ($12.99) and DD would have the Felafel wrap ($8.99). We don't enjoy most of their pastries (too sweet) but would instead choose to have a sweet pretzel ($4.69) and sweet bread ($2.69) from Norway.
The day's total comes to just under $64, plus tax- which, if it's 7%, the day's total comes to $68.50, a savings of $15+. The dining plan would have been $84, and you would have had 4 counter service meals instead of 5 (people forget that the dining plan provides TWO meals per day, not 3). Also, if your daughter isn't a big eater, she might choose a kids' meal at any of these places, which'd reduce the OOP cost. If you were purchasing beverages at each meal, the way DD and I eat would cost more, but we usually just get ice water at QS places. Also, we usually purchase ONE mug to share, for coffee at breakfast (and to more-easily justify it, the money comes from the souvenir budget!). We are park creatures, and oftentimes POP's food court is closed by the time we crawl back from the parks at midnight or later, so no iced tea or soda at night for us. However, even adding in the cost of a mug, I think you'll eat better, and eat more of what you want, for CHEAPER, than using a dining plan.
I'd rather eat OUR Way than Disney's way!