SRB is a marketing and deals man, and he's bloody good at it. He is not an airline manager, and is a bit hazy on the details sometimes! Nevertheless, his commercial instincts are pretty sound. Australia was certainly a long term aim of both him and the company, and there was no way that it was going to be achievable via any other station. It took Virgin long enough to get 5th freedom rights through HKG; it would have been impossible through any of the other ports mentioned earlier.
Virgin did operate a second service to HKG before 9/11, and it's highly likely that that second service will be revived (VS203/4). It won't get a night slot into LHR, so there may have to be some juggling of seats, but one service will remain A346, the other(through) service is likely to be A343.
The DXB service is very unlikely to be extended to Oz at this stage, but there is some talk of a service via PVG to either SYD or Melbourne. How serious this is, I can't say as yet. There are other destinations the airline wants to service before expanding the Australia operation - more Africa routes to mesh with the nascent Virgin Nigeria network are a high priority (think Accra, Nairobi etc.). The airline is also looking at revisiting Toronto and Chicago - the former possibly on a summer-only basis, using the CPT aircraft and slots when they're not being used in the southern summer.