Ontario, the US Northeast and the US Midwest

[King of Kensington]

The million dollar question: would Saskatchewan be Midwestern or just the West?

[botticelli]

Ontario is too big. Anything north of the French River in Ontario should either become its own province (Province of Superior) or join Manitoba instead of being part of Ontario.

as an independent province, it will have 800K people, between Nova Scotia (900k) and New Brunswick (750K).
If joining Manitoba, the new province will have 2M.

[King of Kensington]

I can agree with that. Northern Ontario already functions as a "province within a province" in many respects such as political representation (i.e. riding population quotas are a lot lower than in Southern Ontario).