I can't comment on Gaspe, but can on the others. You will find Ontario to be a different experience than what you have seen in Quebec. I personally prefer Quebec over the area you've mentioned in Ontario. These areas in Ontario are very fast riding, many rail grades, Hydro lines, straight and flat. Hearst, Kap, Cochrane, Timmins, are all very large towns, similar to Chib, or larger. Never been down towards the Sault before, WAWA area looks to be a bit more remote. You should be to the point in the season where traffic has naturally lighted, but weekends during peak season are crazy, especially around Cochrane. Conditions have always been pretty decent, but I can say I have experienced many more miles of plowed roads in Ontario as compared to Quebec, so when the sun shines and no snow, it can get tough going. They don't seem to put much effort into trail reroutes for logging operations or necessary vehicle traffic. Also, IMO, Ontario doesn't seem to take snowmobiling quite as serious from an economical impact as they do in Quebec, so there seems to be less emphasis placed on it. I feel like Quebec does everything they can to get the trails open as quickly as possible and maintain them to the best of their ability as long as possible, where in Ontario, it seems like they simply put it together when the weather is fit, with the exception of Cochrane, they always seem to be on the ball.
Don't get me wrong, This is not meant to bash Ontario, I like both places very well and there is certainly a benefit to the drive when it comes to going to Ontario, I am simply offering up my experiences/opinions on both.
Coming from a guy whose chased snow all over, I would say you don't know what you don't know, get out and try something new, whether it be the Gaspe or Ontario, it's going to be new and different.
Keep us posted on your ride!