All Australian capitol cities are expanding and the new areas are very car dependant as they don't have any decent public transport. By this, I mean a shortish walk to a bus that can deliver them to a decent and fast rail system.
Well, if you want a McMansion in Upper Combuctor West, then suffer. I have trams and buses sailing past my door all the time and it is not too far to walk to the train station. But I pay dearly to live where I live. The expenses are high and our abode is probably a third of the size of your McMansion.
I think while you should pay for some of your public transport through your taxes, and don't forget I am paying them too, it should primarily come via your developer who should be forced to supply everything in a housing estate. Costs you more, costs the developer some profit, costs the local council, ok, that is you again, and it will cost me via my taxes. I am happy to pay my bit if you are.