As _shel mentioned do you have a visa yet? The visa may say where you have to live if it's a work related or state sponsored visa. If you have an independent visa that allows to live and work anywhere then it comes down to where is the work that you do available?
There's an 80% probability wherever you live will be 30 minutes drive from the coast, as that's where 80% of Australians live. Whether that's rural or metropolitan coast depends entirely on what you do for a living.
Then there's what type of climate are you comfortable with, Desert; 50c/122f in the shade, Tropical; 32c/90f and up to 100% humidity, Mediterranean; cool winters < 10c/50f, and hot summers 40c/104f plus.
How many seasons do you prefer in a year; two (wet and dry) or four (spring, summer, autumn and winter).
It really depends on what sort of weather you like/can endure.
Queensland is gorgeous but it's not uncommon for temp's to reach 40+ degrees during the Summer months and the humidity can be 90+ %
The Norther Territory is hot all year round, they just have a wet season (Summer) and a dry season (Winter)
Melbourne is very cosmopolitan (I much prefer it to Sydney) but you can have "four seasons in one day" as far as weather is concerned!