I think I've seen this thread posted in multiple forums alredy. You should really stick to one - so I'm posting a response here in the Star forum.
Sounds like TG is your go for the sole reason of the upgrade awards and most of your flying involving TG to Asia and Europe (and with the rollout of TG's new C and F products, they become quite reasonable to fly as opposed to the nasty old equipment). I wonder if the prices will stay (relatively) low though?
AC is reasonable for the "cheap" status but the upgrade perks once there would be next to useless, and AC only currently flies ex-SYD anyway (the MEL effort didn't last long, alas).
SQ KF might also be an idea specially as you said some of your trips are in C class - you could also go for PPS status that way.
Also LH might be an option given the LH fares being low, and their status multipliers for paid C - but watch out for the low earnings on low fares (admittedly TG also does this now with their V class I think).
On the whole sounds like you've researched things fairly well.
Oh, on the TG issue.. you can qualify for *G by any of the 3 means - ie: 50k in one year OR 80k over 2 or the 40 TG sectors in 1 year. It's definately NOT all 3.
Enjoy your flying something other than QF9 MEL-SIN
