Thanks all for your input!

I was doing the routing on great circle mapper, and there's really not a huge mileage difference between the various methods of getting there -- guess that's what happens when it's as close to the opposite side of the world you can get without landing the in the Indian Ocean! CX does net me an extra 5-6k RT, but would require the hassle of connecting through Vancouver.

I think I'll try with BA. Was able to book their PE on a Europe trip last year, and even got a LHR-SEA operational upgrade to Club World out of it when an entire athletic team of wheelchair-bound individuals had to be accommodated. Will keep my fingers crossed for continued good-BA-karma this year! I'm actually going for an Africa Summit of the Special Olympics, so luck may be on my side again!