Our summer home is on Moosehead Lake some 90 miles north-northwest of Bangor. My family has been in that area since 1887 so we're comfortable not being on the coast. That said, parts of coastal Maine striking and are worth visiting. Depending on the time of year (and the weather) some coastal towns and villages can be crowded and finding parking can be a major challenge - Bar harbor, Camden, Rockport come to mind. All are on US Route 1 which in the summer is a parking lot that moves at about 5 miles per hour.
Our favored coastal places include Rockland, Stonington, Lubec, and Eastport. Rockland, south of Rockport and Camden, is home to the Farnsworth Museum complex, the Maine Lighthouse Muesum, "The Morning in Maine" windjammer (offering bay cruises), and is close to the Owls Head Transportation Museum which features antique and vintage motor vehicles, motorcycles and aircraft - all of which are functional. Stonington is officially a working fishing village but quaint and interesting without being crowded or overly expensive.
Eastport and Lubec both lay claim to being the easternmost point in the U.S. and were once very important fishing centers - lots of fascinating history. Of the two, Lubec is easier to reach and offers easy access to Campobello Island (Canadian) where Franklin Roosevelt's summer "cottage" resides. That, of course, requires a passport. Lubec is also the home of Monica's Gourmet Chocolates, and the Home Port B&B, both of which are genuinely excellent. Each village also has loads of local shops and restaurants worthy of visiting.
Moosehead Lake is, not surprisingly, among our favorite locations (since we live there every summer) and includes the town of Greenville at the foot of the lake, the village of Rockwood on the western shore and Kokadjo on the eastern shore. Lily Bay State Park is also on the eastern shore.
Activities include hunting, fishing, hiking, water sports, ATVing (is that a word?) and the opportunity to cruise the lake aboard the Katahdin, a 1914 vintage vessel that is now operated by the Moosehead Marine Museum. It's also home to the Moosehead Historical Society and Museums which offers tours of a lumber baron's mansion and Lumbermen's Museum. The second weekend in September features the annual International Seaplane Fly-In, now over forty years old and still going strong.
This probably qualifies as too much information, for which I apologize but it's my official home and, well, you did ask.
PS - Quebec City is about 150 miles north of Rockwood and is both beautiful and charming. Further, we spent some time in Nova Scotia this past summer and, though, something of a journey to reach, it's spectacular.