It has been nine years since we've been there, but the roads were fine. Stayed at Marco Polo on Prince Edward Island (PEI) and recommend it. We weren't camping when we were in Nova Scotia. There's a KOA at the head of Fundy that looks good. We're looking at that for our return trip. There was a municipal CG in St John, NB, which was terrible. Greeted there by a big sign announcing a "Boil Water Alert". Mainly a place for traveling workers. Nice town otherwise.
But, that said, there's all of the Titanic stuff in Halifax, and a good museum. Not to be missed is Badeck where Alexander Graham Bell summered and experimented with hydrofoil boats on Bra d'Or lake. Wonderful museum there of his work. Louisburg is a recreation of the 18th century fort which was at the center of the Louisburg Expedition military campaign. And, of course, you have to see Fundy where you can actually see the tide go in and out. The tides are in excess of 9' (twice a day), so the water level changes more than a foot every hour.
Enjoy.
Fred.