Vancouver should be much more concerned about the Calgary - Asia flights, the pledges for more when the 787s come than Toronto flights. Toronto flights to most of Asia make sense since the range is there, the market is there, and due to circle routes if you can get a high enough load factor you save a set of landing fees and somewhere around 800 miles.
The Calgary flights skim off higher fare customers that could contribute to more Vancouver flights. The Toronto flights are there in their own right, as Air Canada tries to prevent eastern Canadians from connecting into international hubs that have flights to almost everywhere, like New York.
Flights to New Delhi for example, with the circle route Vancouver only has a 300 mile advantage. Why should the air line waste money by routing them through YVR? Very different for Tokyo (YVR advantage 1800 miles) where the transfer only adds 300 miles, or Seoul (YVR advantage 1500 miles for a transfer penalty of only 500 miles.
You need to think of the globe as a sphere, not a flat map before proclaiming it logical to hub through Vancouver.