Originally Posted by Santander

That should clinch it alone. ~$3.5k r/t from east coast NA to Asia is very reasonable, especially considering AC C is better than both UA and CO. You don't have to go all the way out to EWR or JFK either.

I was actually going to suggest looking at CA (not fully flat, but often has very reasonable C fares) but since AC is so cheap I'd jump on it if I were you. Sure NH and OZ are good, but it's more convenient to transit YYZ while you're still fresh than stumble around NRT/ICN like a zombie while you're hungover from all the wine you drank in-flight! The CX suggestion is too inconvenient imo, if you want to connect in Asia enroute to PEK it's better to do it in NRT or ICN which are at least sort of "on the way"