Cape Breton - the Cabot Trail, and North of it (forget about Sydney and Glace Bay).
Bay of Fundy - especially Burncoat Head (come at low tide with rubber boots, go for a hike on the Ocean floor, go for lunch, come back for the high tide)
Brier Island
Quebec City
Iles de la Madeleine (yes, Entry Island is worth the daytrip - unless you are restricted in your mobility)