I am planning a trip in early autumn 2012, SEA-PER, then PER-SYD, followed by a few weeks in SYD with possible side trips to MEL and BNE. Looking for discount business fares and willing to use miles for part of the trip if that is worthwhile. All my miles are AA so I doubt I can use them to upgrade.

One possibility is SEA-LHR-PER on BA, and then PER-SYD-SFO-SEA on QF. Not sure at this point whether I will fly SYD-BNE-SYD as a side trip or SYD-BNE-XXX-SEA for the return. Same for MEL.

Could also do CX from Vancouver, but that is less convenient than the SEA-LHR flight on BA.

Any help in getting started with options would be much appreciated.