Is LTG worthwhile any more?
I am stranded on LT silver (combination of QF not flying in New Zealand any more and my flying habits changed). I thought about doing a status run a while ago when there was a double SC offer to get me a year of platinum and up to LTG.
I'm also sitting here with enough points for 280K Oneworld explorer in J for mrs jaybeedee and I but no chance of getting award bookings.
Have now shifted my points/status credit activity to Air NZ where the use of points is transparent and we have been able to use both recognition upgrades and one-up upgrades as well as buy fares for the kids at sensible prices.
I got spoilt getting J award bookings being WP and Partner Gold, but my perception is that you have to be able to be WP to phone the call centre and get award flights cleared
Opinion only:
Based on what you've written re your current travel patterns and preference then stick to NZ if that suits your needs.
It may well be QF will try another double SC offer at some point to target NZ res and you could potentially take advantage if personal plans work out (eg: a trip to oz or beyond, for example).
You will have (in theory) LTS as long as you remain a QFF member, so the option won't go anywhere, and your habits may change again and you can always revisit this option* in the future
It also depends, I guess, on how far you have to go. from your post it sounds like you're ~1500 SC or fewer off LTG which is something you can always do in dribs and drabs - eg: say a trip to the USA on NZ, you could do some internal flights on AA (I do realise that NZ partners with UA intra-USA). and build up slowly.
to me the benefits of LTG probably sound different to yours, which seem to be based around award availability and possibly upgrade options whereas I see the value in terms of things like OWS(Sapphire) status allowing lounge access, free bags (intra USA and possibly elsewhere) and priority boarding, check in and the like. Most of which one could get on premium fares (or award travel in premium cabins) anyway. So, it probably comes down to, as you say, the reduced ability as a QF Gold to get award seats and upgrades so it may not suit at this time to go for it.
I actually have a similar situation with headed to UA LTG which I am doing in dribs and drabs when fares and travel suits, but not going out of my way to go there if QF/oneworld is a better option for me (since QF is still, more or less, my main program). It may well be a similar approach for you at this point in time
my 2 cents
(* subject to terms and conditions, which may change

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