I think your best bet is to book 2F and 2 J each way for DUB/DXB/SYD each way (280000 miles one way) and swap the premium seats on the return (as long as you can prise out the pair who enjoyed it outbound!). If more F awards open up you can always upgrade but you will have to start looking the full 330 days out as QFF have a bit of a start on you. I would forget the stopovers unless you restrict them to less than 24hr or use a lot more points.
As an example (QF online) you could book EK162/QF2 for 2 F on Mar 11/12 2014 and also 2J with a connection in LHR.
Hope this helps.