OK, how about:
syd-per-mel-hkg on qf for 8312 actual miles but only 5818 AA miles
hkg-icn on cx for AsiaMiles credit
icn-nrt separate AA JAL codeshare ticket for 782 AA miles
nrt-sjc-lax on AA for 5462 AA miles
Now you are AA Platinum.
As for the rest of the trip, something like this might work:
dfw-mia-nas-mia-sdq-sju-dfw-{europe]-lhr-nrt-syd
Problem is that with today's schedules you won't get an overnight in nrt as the syd flight leaves at 2045 but the flights from lhr arrive in the afternoon.