Convenience’s sake, there are no direct flights with ANA to Toronto or Montreal, so you would need to connect to a US hub or in Vancouver. I would personally choose JFK, IAD or ORD over YVR, since it would limit your sleep onboard.
Connecting from those US hubs, you would use a Star Alliance (United or Air Canada) to either Toronto or Montreal. In terms of convenience, a direct flight to Toronto/Montreal is better, but would have to be on AC and the onboard experience would not be as nice, especially if you can get a flight with “The room” and AC can’t beat ANA’s hospitality. PE would be similar, but ANA has a smaller economy cabin, so access to washroom and overall capacity will be much better. That’s my take.