If you are coming from a big city, crowds are not bad.

Ogunquit + Acadia here. Thanks for all the tips! I was thinking that we could use the Island Explorer to avoid dealing with parking in Bar Harbor. Do the buses get crowded though, like standing room only? I was envisioning - if the crowds were really bad - standing in line for the Island Explorer, then possibly having to wait for the next one (thirty minutes later), like some Metro stops at rush hour.

For our first time I'd prefer to stay on the non-quiet side, but if the crowds are as bad as that, then I'd definitely look at rentals on the quiet side only.