Like any place on the ocean, NS has many beautiful as well as historic locations that make it hard to do justice to them in one trip. We've been there 3x and still haven't driven up the NS shoreline of the Bay of Fundy--highest tides in the world and truly impressive to be chased back to high ground by them. Landlubbers really need tide tables and it's amazing how quickly one adjusts to this rhythm of the sea even while visiting. Camp at Fundy NP in NB for at least 2 nights to allow time to appreciate the tides. Buy a NP pass at Fundy (or the first park you enter) if you plan on visiting a number of NP and NHS. Be careful though, there are several levels of passes--tell the ranger where you want to go and make sure the pass that covers those parks is worth it. The last time we were in NS we bought the annual pass for all of Canada--valid for 12 months from date of purchase--and it was more than worth it, but it is more expensive than the US Parks one. Here are all the fees and the link to the national annual pass is a couple up from the bottom of the page
This is the main Parks Canada page where you can find details on any park or NHS you intend to visit:
and the NS tourism page: http://novascotia.com/en/home/default.aspx
This is a really picturesque place to kayak on the Bay of Fundy: http://www.thehopewellrocks.ca/English/index.htm
In Halifax, camp on the Dartmouth side of the bay. Like most seaports, Halifax is a real pain to drive in, with expensive parking--think Boston, only on a smaller scale. You can park and take a water taxi from Dartmouth right to downtown Halifax for a fraction of the cost and aggravation of driving there. For a day trip, take the expressway to Lunenburg http://www.lunenburgns.com/
and then drive back on the coastal highway. ln Lunenburg, spend a good part of the day at the waterfront attractions and restaurant and St. John's Anglican Church. On the way back to Halifax, put the kayaks into Mahone Bay for some spectacular views of the town and its 3 waterfront churches. Some think Peggy's Cove, also on the coastal highway, is overhyped, but it is a truly beautiful spot that I wouldn't miss.
Fortress Louisbourg is a smaller attraction similar to Williamsburg, VA. Only a small part of the fortress has been excavated and restored and its older, 1730's, French frontier location gives it quite a different flavor than Williamsburg. Well worth camping in the area and spending 2 days to see it.
Don't drive the Cabot Trail in one day--the locals will laugh at you--besides, it's a very scenic NP with camping and hiking trails and another spot you can't get around well with a trailer in tow.
NS has coastal weather very similar to the US northeast. Build in some flex for rainy days.
When planning a trip, I always start with the Rand Mcnally or Trailer Life atlas and look for all the "red print" points of interest. I also do a lot of research using Google and send away for all the state/province travel guides. Using Google you can also find various city pages, like the Lunenburg one above. We do as much solo driving as possible--and you'll definitely want to do that in NS--and if we are in our destination state/province will not drive more than 200 mi a day towing or solo. If you've been to the coast in ME, NS is not a lot different--you definitely don't want to be towing a 2570 while looking at scenery or looking for a place to park to take a hike.
Feel free to pm me if you want more info.