Sunset Point Campground is a lovely place. The sunset over a muddy bay at low tide was unique to us, as was the clammers plying their trade. And the campsites were very well kept, and had a roof over the picnic tables. Very down-home, inexpensive, and with very gracious and helpful hosts.
Acadia Park is grand. Don't miss it. If you only do Bar Harbor, you don't see the REAL Maine. Bar Harbor is just another place to get chinese t-shirts of a different color for too much moolah, and very crowded.
Machias, Eastport, Whiting etc, are further along the coast. Lower prices during peak season cuz there are so few tourists that go there. Blueberries $2.75 a qt. Great lobster rolls, 2 for $12, lobster right off the boat. We go out to eat where the locals do, not the tourists.