Tips - start the paperwork (validation, security) way way ahead of time. It may take ages. Last time I checked, around 170aud/hr for something like a C172.
Where and what depends upon your experience, desires, and nav competance / ability. It also (massively) depends on the season, and where you are in the country.
Sydney's victor 1 is well worth doing (harbour scenic, and low level coastal). If you're used to the eurozone, you'd be amazed where you can fly.
Otherwise I highly, highly recommend the outback, it's a different world. But that would depend on personal comfort levels, and how happy you are being away from the world.