Go to Portland and take route 1 to Bar harbor from Brunswick if you're not in a hurry. Traffic will be horrible that time of year anyways.. so the extra hour or so shouldn't make too much of a difference. That way you'll see the other coastal communities (many better than Bar Harbor).
Portland has great food and drinks and would be a great place to stop for a night on the town. Definitely check out the Old Port - lots of cool old bars, restaurants, and microbreweries all within like a quarter mile stretch.
The Park Loop Road in Acadia is awesome! It's windy and twisty and mostly one-way so you don't have to worry about traffic coming around corners. The road is also very good quality as it is closed during the winters. The views are amazing. Be sure to take the switchback road up Cadillac Mountain as well - also a fun road with some great views! There is 25-35mph speed limit, but as long as you're not driving like a complete mass-hole
you'll be fine.
Let me know what route you take though - I'm planning the same trip in reverse! My brother goes to school at Hobart in Geneva on the Finger Lakes and my Dad's side of the family is in Pittsburgh. The final destination is Pittsburgh, but if I go out during the end of the summer, my brother will be at school for pre-season.
If I think of any other fun roads on your route through Maine I'll write back. Cool trip!
