In answer to one of your original questions, I was out east last October - NB, NS, Gaspe, entered at Houlton Maine in a 27' class A gasser pulling a Wrangler, and I thought some of the roads were OK, and some were terrible, compared to what I see elsewhere in Canada, and here in Ontario. Not as bad as northern BC and the Yukon in 2016, but they're not far behind. Just my opinion, and I admit it is a subjective thing, but I've driven all over the continent, so I'll add YMMV. Even the year before (2016), they weren't as bad, so maybe time and wear and tear is taking it's toll on them. I did see plenty of construction, particularly in New Brunswick, so at least they're addressing it. Gaspe Rte 132 is a nice drive as well, and it's always under construction somewhere.
I also have noted some folks mentioned the Cabot Trail. I would not recommend driving it in a 40' diesel pusher, whether pulling anything or not. If you decide to do Cape Breton, and the Cabot Trail, it is a really nice drive on a clear day, but not in anything bigger than a pickup truck, class B van, or a smaller (<25') class C. Some sections of the roads are narrow, there are sharp turns in places, and one or two grades that are simply "challenging" near the northern tip of the island. We didn't do the Cabot Trail in our class A with toad, but have done it in our class B van 3 times. There are places in Port Hawkesbury where you can drop the MH, and do the island in your toad.
One last comment, northern/eastern Maine near the Canadian border and anywhere in New Brunswick, are two of the best places to enjoy the leaves changing color.
EDIT: One more comment - do the Hopewell Rocks on the Bay of Fundy in New Brunswick. "Walk on the ocean floor". It's pretty interesting.
Mike. Comments are anecdotal or personal opinions, and worth what you paid for them.
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 Wrangler JKU (sold @ ????)
2016 Sunstar 26HE, V10, 3V, 6 Speed (sold @ 4600 miles)
2002 Roadtrek C190P (sold @ 315,000kms)