With the start and end cities in Season One being Melbourne and Perth, you would expect places like Brisbane or Sydney to be used next time.
However, I think it will be highly likely that the race will once again travel a full circle up to Europe and back again, without crossing either the Atlantic or Pacific. With that in mind, I would be surprised if they began and ended on the East Coast as flights up to Asia and elsewhere would be more expensive than the East.
Seeing as Perth is the only decent sized settlement on the East Coast, I am almost certain that it will be used as one of either the start or finish line. And I also doubt that TARAus would use the same city in the final episode twice, so my money's on Perth being the starting city.