To a prior poster: If you are on one of the Dining Plans, Disney completely enforces that ages 3-9 can only order off the childrens' menus and almost completely enforces that ages 10+ can only order off the adults' menus.
To the OP: Buffets are lifesavers to people on the
DDP who have under-10 kids with big appetites. They are the kiss of financial death to people paying OOP with 10+ age kids.
There are lots of cool TS and CS restaurants on property. You can split orders, order only apps, or do pretty much anything since you are paying OOP. It sounds like you are looking for meals that include some type of entertainment/experience.
Any of the AKL restaurants will give you the chance to also see the animals at the AKL savannahs, which are different from the AK park. Sanaa is the TS restaurant; check the menu to make sure it would work for the pickiest eaters.
In Epcot, Coral Reef is fun to watch the fish - you're inside the aquarium, basically. Marrakesh has some music & belly dancing.
We love Ohana but, again, this may not be a good $$$ decision for you right now based on the kids' appetites. Maybe save it for another trip a a few more years down the road (got to plan ahead, you know!). For similar polynesian/pan-asian cuisine you could try Kona, or better yet grab dinner at Captain Cooks (CS at the Poly) where you can get Dole Whips for dessert. Time it so you take them outside and eat them on the beach at the Poly while watching the Electric Water Pagent and/or the fireworks over the MK. You can also get similar cuisine at Y&Y TS in AK.
The one restaurant that might be a good compromise is WCC at WL. The large eaters of the group can get the bottomless BBQ skillet dinner (and if they're really ambitious, the bottomless milkshake to drink). Everybody else can just order off the menu, split an order, just have apps, just have the milkshakes - hey, you're on vacation. Whatever.
Some CS locations that give you more of a sit-down restaurant experience at a lower price would be Sunshine Seasons at Epcot and Pepper Market at CSR.