About QF. Not sure about higher classs but for economy to me QF is QF, not an alliance. If you are with the QF program you get 100% of miles if you fly with QF. If you fly with CX you get 50% of points. If you go with BA (British Airways) you may get only 25%.

One adv with QF is that if you can stick with QF which basically means no direct flights to HKG. They do have a bonus earning points if you get higher status.

The award rates isn't that great not sure about upgrades. With the bonus I guess it's quite good actually then ...

You could join SIA or ANA, good rates for awards that I know for economy. They SIA I know have 3 tiers so maybe that means greater success when securing dates you want - maybe something like ANZ's standby and confirmed upgrades I guess..... 3yr expiry. The thing is check out whether the economy fares to TT will get you points to these other FFPs .... it might not.

Air Canada is quite good for awards too like going to HKG from AKL at least on economy. But like United Airlines, AC you need to do a few flights on their metal before you meet the min requirement to get higher status. AC also has a healthy bonus I think up to 50% (total).

SIA gives 25% bonus.