The A380 works if you can fill it and fly sub ten hour sectors. If you can't, the 330/350 is the better choice.
The 777 is a long haul aeroplane. It's the aeroplane QF should be flying the pacific in.
QF should also have a combination of 330s and 777s hubbing to Dubai, with 380s flying the onwards connection to Europe. It's the ideal machine for that, which is why EK love them.
I have a feeling that's what the end game is. 787s and 330s to Dubai from all australian capitals and the full LHR slots being utilised onwards with 380s allowing more capacity for both QF and EK.