I've never used the dining plan. Honestly, it's way too much food, and it's not the way we eat.
My family like to split a couple of appetizers, and everyone gets their own entree. Dessert could be at the restaurant if something looks good, but we can also wait a couple of hours and get something elsewhere. Apps aren't included on the regular or plus dining plans, which is a bummer. We're also not necessarily married to getting the steak-lobster-shrimp to maximize the plan credit. Sometimes we want chicken or *gasp!* a salad for dinner! None of us are drinkers, so we would also lose the benefit of the alcohol credit.
Since my children are older, we don't need to go to every AYCTE character meal, which are a great use of dining plan credits, but really expensive out of pocket for what's fairly mediocre food.
I do the same thing you're thinking, load a gift card or two with the value of the dining plan, and use that to pay "out of pocket". It works for us. At the end of the trip, there's like $200-$250 leftover on the card, and instead of being stuck with a bunch of snacks in a "use it or lose it" mode, that's a shopping spree at Mousegears or The Emporium before going home.