We took our 2 teenagers to St Stephen for a family vacation this July. We had rented a private home overlooking the ocean near the town of St. Stephen's. We had a wonderful vacation as a family but I write this review about the area attractions as there really aren't any. Although St. Stephen is known as the Chocolate town of Canada (it has home to Ganong chocolates) there really isn't much to see here except the chocolate (good but very pricey). Actually, we found this trip to be very expensive all around. It may have something to do with the proximity to St Andrews, known for being the most beautiful town in the maritimes (which I disagree).
So, if you're looking for peace and quiet and have found really wonderful accomdations that don't require you to need much sightseeing than yes, this is a lovely place to visit. But we wouldn't recommend it for families who need lot's of external stimuli - you won't find it here.
Also, take note that we found this area (St. Stephen's to St. Martin's) to be expensive (particularly the food, considering almost everything is deep fried). Just ensure you budget accordingly.