I'd do it differently. Station the jet in Porttle overnight. Do a morning departure ex-Porttle in the morning around 8-9am, which gets into YYZ in the mid afternoon to connect to the Europe flights in early evening. The return ex-YYZ will leave early evening, with connecting traffic from Europe.

For OandD traffic, I think business men tend to avoid red eye eastbound. Morning flight eastbound is good. For westbound, I prefer to take an evening flight and stay in a hotel overnight and feel well rested before doing business the next day. Doing a morning YYZ-west coast flight, you gain a lot of time during the day but the long day gets very tiring.

Looking at the west coast city, I think the most viable city for AC to operate a flight from YYZ is probably SJC. I see most people on AC SFO-YYZ are doing tech business in the south bay area.