You know the deal from here: https://www.ozbargain.com.au/node/97476
I constantly had a look at the flights. Whilst the prices constantly change, the offer itself is still available and I just booked flights to Germany ( SYD - SIN ( with Scoot ) - FRA and back DUS - SYD ) for 650€ with the Etihad flights costing 510€ and Scoot to Singapore for $159 + luggage in May/June - can't complain.
The link for the offer is the flight I booked. If you play a little with dates and destinations you might get it cheaper. For example I first tried to and out of Frankfurt, but leaving from DUS was a bit cheaper. German airports were the cheapest I found, but again, try your luck.
So far I had only great experiences with Etihad, nothing to complain about.
I was lucky enough to have some savings in € as the AU$ is unfortunately going downhill atm.
Update: Please note that the prices mentioned in my deal are not available through the link anymore at the moment. However, if you keep looking you will hopefully find a good deal with different days / airports or a few days from now. Basically this is just here to give you an idea of how these cheap prices work. I've been following the previous deal and flights for about a year now and they constantly went up and down.
It's a very nice price. I am always scared of using two airlines on such a long flight (when one is delayed you miss the other flight and can't get any replacement flight … you need to pay again). A stopover helps to reduce the risk.