My normal experience of entering China is always fast and courteous, entering the US is frankly scary every time, lots of questions about what you're going to do - I show the same business APEC card at both borders (unlike China it's not a visa for the US border, the US is not a full member of APEC, but it does get me in the crew line, and identifies me as a frequent business traveller)
Have you tried the ANZ AKL-YVR connecting to ACA YVR-Europe flights? Canada is far happier about transiting passengers than the USA is. (And if you've tried it and didn't like it, I'm curious why.)
I haven't tried Vancouver, maybe next time - I do prefer long flights that are overnight so to Europe that means with a daytime (or two) somewhere in the middle
The whole 360 body scan and the random questioning by US border control is simply terrifying. I have been asked to spell my name and say my birthday to see my reaction. It’s just an uncomfortable experience in general. I can’t even imagine what treatment middle easterner will get if even I get that treatment.