The problem is there's no star alliance flights within Australia.

As such, the only real solution is to fly YVR-Auckland-Perth on Aeroplan, and then buy a roundtrip ticket from Auckland to Melbourne on a low-cost carrier, or do the same from Perth (but since that's cross country, flying from Auckland would be a shorter flight).

Stopping in Hong Kong on the way back is trivial through Bangkok or Singapore

I did YVR-PER (destination)-HKG (stopover)-Tokyo (stopover)-YVR, with a 5 hour layover in Auckland and 20 hour layover in Bangkok last year.

You won't have enough points for business class though, Australia is 135k miles each - you'll need another 20k somehow (or pay to top up). I don't know if there are any seats left on business class on such short notice either