Acadia: Bar Harbor KOA Woodside. Get a place out back in the grassy asea. Bring DVDs as TV is minimal.
Mid-coast: Saltwater Farm in Thomaston. Great location for visiting Camden, Rockland, Owl'S Head, and lots of little places.
Red's Eats in Wiscasset: decent food, but a horror if you're towing anything. No place to park except along the river and you won't find your way there on your first visit. Better to stay at Chewonki CG just south of town and see the town properly. Two great historic homes in town to visit.
Forget Old Orchard unless you like crowded, noisy CGs. Beach is good, but the rest of it is like a carnival.
Don't go to Ogunquit driving anything bigger than a Vespa. Nice town but a traffic nightmare.
Fred.