Welcome, you have made a good choice!
Most of Australia's population is in the state capitals (Sydney 6m, Melbourne 5m, Brisbane 1.5m, Adelaide, Perth and Hobart 1m each). Adelaide, Hobart, Canberra or Darwin will bore you to death. Perth is the best place to live if you are into nature sports (it reminds me of San Diego), but it is by itself on the West coast, and not exactly a media capital. The West coast is less developed and crowded than the East coast, and has lots of natural beauty close by the city. Brisbane has the best weather, but not much else, in my opinion. Most of the Indian/Pakistani community is in Sydney (more families) and Melbourne (more students). Sydney has arguably better weather, and Melbourne does get cold, but nothing worse than Islamabad. It doesn't snow in the major cities -- only in some outer suburbs. I find Sydney to be a generic big city -- fast, dirty, crowded, noisy, expensive -- and Melbourne to be much more livable. If you can get over the weather -- buy a jacket, big deal! -- Melbourne is a much more livable city. It is more relaxed and feels like a small European town despite having all the conveniences of a major city. Sydney, on the other hand, has lots more jobs and commuting to the CBD (central business district = downtown) by ferry is a pretty cool experience!
Australian culture is much less 'sensitive' than US or UK. People here will make jokes that would raise eyebrows in the US, but the Aussies don't mean it negatively. It's more of an attitude of not taking things too seriously.
As for crime, Australia is a very safe place. Naturally, you have to use common sense and avoid poorer neighborhoods late at night, but those neighborhoods are rare. Most places are safe.
Finally, although cricket is popular, it is not the number one sport. In Sydney (New South Wales), people like rugby, and Melbourne (Victoria) is crazy about Footy.
