Didn't realise Vaus was daily BNE-LAX yet, however Vaus website shows dep BNE1100 LMT arr LAX 0700 LMT, Dep LAX 22:30 LMT arr BNE 0520 LMT. The flt you're talking about is SYD-LAX
I agree that later arrivals into LAX are much harder, QF AKL-LAX typically gets in to LAX around midday, and you are totally buggered. It really depends on sleep periods, you need to get 2 sleep periods, one to get over the flight, then another good rest to prepare for next flight. This would be achieved in a 28 hour slip, but a bit hard on the crew, you be in bed for about 16 hours with a few hours to eat. So SYD slip would probably stay the extra day.
As for squeezing in more flights, if you are on 38 hours slip arrive morning and dep the following evening and sleep as I referred to in my previous post you basically stay on sydney time. The jet lag is minimal and you recover fairly quickly. However, if you have a longer slip and do a bit of sightseeing during the day, prepare to pay the price at home. Basically in LAX, sleep during the day, awake at night.