MK - BOG lunch, Columbia Harbor House if your GS likes seafood, Cosmic Ray's for sheer selection, Pinocchio Village Haus to sit and wave to the voyagers on IASW. (Kids love this!)
HS - Backlot Express has the most kid friendly options imo
AK - Flame Tree!
Epcot - Sunshine Seasons, or just snack your way around WS.
We've done QS only trips. It does take some stress off and reintroduces a little bit of spontaneity back into WDW.