While I would love Australia, I figure it's fairly cost-prohibitive for most of us
Speaking from the Tennessee contingent, we (Memphis) have a major airport, multiple major interstate accesses, even a train for those so inclined (though I confess I don't know what points it connects to). From a seasonal perspective, it's far superior to the other choices in terms of weather, as freezing temps are the exception, not the norm, even in January (average highs are around 50 degrees Fahrenheit). Fort Wayne = Winter Fantasy? Seriously? Who ever came up with that crap, lol?
The city hosts multiple conventions throughout the year, so there's no shortage of hotels in the area. Food, for the most part, is relatively inexpensive, running the full gamut of prices and cuisines. It's centrally located, so many of the Americans (with the exception of the Detroit area folks) can probably get there with a reasonable drive. There's also quite a few of us locals who would be willing to provide cheap taxi services to and from the airport and/or hotel.
That's my two cents