A FlyerTalk Posting Legend
Join Date: Sep 2012
Location: SFO
Programs: AC SE MM, BA Gold, SQ Silver, Bonvoy Tit LTG, Hyatt Glob, HH Diamond
Posts: 44,313
It sounds like most of your complaints are about the FA, and would therefore be more appropriate in the UA forum.
For the rest, I feel like you're better off comparing UA SFO-YYZ to AC YVR-BOS or some other non-PLH, non-Signature route, if you just want a "transcon" comparison.
If you want to make this a SFO-YYZ comparison, then that's fine, but AC wins in pretty much every respect there, without even thinking about lie-flats.
In terms of being asked your "second choice", UA just does it differently. Rather than zig-zag through the cabin, they go front to back and then figure it out in the galley. Given the complaints I've read on this forum about the zig-zag behavior on AC, I can definitely appreciate why they do it differently. I'm not sure which I prefer.