I was in a similar situation a few years back. Ended up living in the UK for 4 years.
I recommend changing to BA.
1) Better avios earn on BA flights (compared to QF points earnt)
2) Better perks being BAEC flying BA. I was BAEC Gold and received about 6-8x more upgrades to J and F compared to my current Qantas Platinum One flying mainly Qantas. (The BAEC equivalent of P1 is Gold Guest List, I was just a gold)
3) Lifetime status credits for BA - they offer lifetime OWE but depending on your flying habits could take a while to reach
4) If you apply for the BAEC premium amex card (annual fee GBP100 or 150) you get a free voucher every year: make an awards booking and receive another identical ticket free for the same trip. That means if you book LHR-SYD return in F on points you get another one for your travel partner on the same flight for free.