I know nothing of canada, other than it doesn't seem to have a culture distinct from our own and it has a nasty climate, but I'm sure you can find some canadophile to pick apart your predictions about our northern neighbors. Seems that you should color the western provinces (except BC) the same as wyoming and idaho, given recent trends. The same sorts of rugged individualist small government gun nuts who move to the rockies in this country seem to be attracted to the western extremities of the northern great plains in Canada.
No reason to be making fun of Canada. Especially about Culture, that's a raw nerve. Canada, even back way when already showed signs of its... divergent leftness? What an interesting term, can I copyright that? The Canadian Socialist movement began in Southern and Central Alberta and quickly spread throughout the West, so much for that right minded western Canada theory, it wasn't that way early on. Canada at this stage would likely be for strong centralized government, and be less concerned about individual state/province rights. Canada is a Federation after all, despite what people in Alberta and Quebec want. I also wanted to point out that the proper terms for people from Quebec is Quebecois, or in English we usually call them Quebec(k)ers.
I think that I should point out that keeping an Empire together like this at this period in history would be difficult, perhaps the early advent of the telegraph (I'm not sure when it was invented) or the telephone (Invented by a Canadian in the late 1800's I could get a date for you) could alleviate some of these early problems. And given that the Natives in this timeline didn't just flee into Canada you've got thousands of pissed off natives waiting for you in the West, I.E. there's trouble a-brewin'.
Siege