I completely agree about the benefits of focussing on one alliance. If One World had a Canadian partner, I’d probably fly on them.

When I mentioned “better” partners, I was referring to the quality and service, not the rewards earning potential. As you pointed out, most people would prefer to fly on DL over UA. From my reading, AF-KLM provides a better experience than LH. I have never flown on LH though so I can’t speak from personal experience. LH J class seems to get constantly criticized in reviews.

If I fly to Europe from YYJ, I can connect on WS in YVR to AF to CDG or KLM to AMS and then on from there. With the new WS AMS service, YYJ to YYC to AMS on WS then onto the final destination on KLM is also a possibility.

I mentioned DXB and EK only because I’m planning a trip there next year. It’s not a frequent destination for me. However, I’d be remiss no to fly there on EK J class given the generally great reviews they get and earning some points on WS would be a bonus. I agree that the codeshare flights between WS and EK are limited. I’m hoping that will change before I need to book. If AS and EK were still partners, I’d probably go YYJ to SEA to DXB rather than through YYZ.