I keep it short and sweet, Yes its a long way to go for reference and location research however the Pakenham line in Melbourne would offer a great ride with a wide variety of rolling stock used on the line and freight as well . A wide array of stations and its undergoing major upgrades with there "skyrail" project making it rather interesting line visually and functionally. For reference : http://www.metrotrains.com.au/lines/pakenham/
Hello, Australia has already been confirmed from DTG that it will not happen due to specific licensing problems.
I'm just copying that out of the thread you mentioned. Quoted from a user and, yes, there's plenty of discussion of DTG's difficulties in acquiring a license for Australian brands. That's a shame.
But heck, this is the kind of thing where I'd call DTG insane for letting no branding stop them. They'd probably make a lot more people happier by releasing an unbranded Australian DLC than another branded American DLC.