Both of my suggestions were given. Gray's manor in South Port is very nice. Lake Pemiquad on the next penisula North is great too. But my favorite is in far DownEast, and Gary already said it: Cobs Cook. That area is so beautiful. Most people say "it is such a haul", but the haul is worth it. Once you pass Bar Harbor the real beauty of Maine will be all you see. I strongly encourage you to reconsider the distance you are willing to go. If you do, make sure to check out The Sardine Can Factory Museum
in Lubec. It was one of the coolest homespun museums I have ever been to.