Bar Harbor is a delightful town and the gateway to the sensational Acadia National Park. There is a free bus system that departs from the town green near the visitor information center; it includes an assortment of loops going through the park and permits "on-and-off" privileges to allow for more extended viewing, hikes, a visit to Jordan Pond and tea at the lodge, etc.
The port in Halifax was a change from a planned stop in Lunenburg, which was not communicated until we were already underway. Lunenburg is a UNESCO world heritage highlight; many tour companies offer day trips FROM Halifax to Lunenburg, so we were disappointed in this change. Furthermore, we had arrangements made in Lunenburg and no easy way to investigate options in Halifax from onboard, other than the costly cruise excursions. Crystal made no accommodations for free internet use to investigate alternatives. We did disembark, took a taxi to the Titanic museum, walked along the boardwalk and saw the marketplace, but it was not noteworthy.
While we didn't go on a cruise tour, we used Roys Tours http://www.roystours.webs.com/, and would not recommend it. Roy's banter failed to emphasize the noteworthy aspects of the town and surrounding areas, and he opined about political issues inappropriately, displaying an unsavory racist intolerance. We didn't really see the Bay of Funday tides because of the timing of our trip in connection with high/low tides, and basically didn't hit many of the highlights shown in his website description. Difficult to get in and out of the van on mediocre stops we did make, mostly at places where he clearly wanted us to buy thing so he could get a kickback. If there was much to see in St. John's, we certainly didn't see it. Very disappointing.