I can scarcely come up with a list of any reptiles which definitely could not survive in Australia. Australia has virtually every climate and habitat type other than permafrost (which reptiles can't live in anyway).
Australian herpers wanting to keep exotics tried to make the case that tortoises couldn't survive in Australia, 'I mean, just look at them, they can barely move, they're so slow, they have no defenses' etc etc, totally ignoring the fact that these animals thrive from Africa to Asia to America in the wild, managing to deal with wolves, lions, bears, etc.
Import laws aren't your only obstacle. We can't even import native species into Australia, that's how strict it is, but there is also a blanket ban on the private keeping of any non native reptiles and amphibians. Neither import nor exotic reptile keeping laws are going to change in Australia. As a lifelong keen herper and a qualified ecologist, I'll say this is one of the few cases of the Australian law actually getting it right.
Oh, to give you an idea of how strict Australia is (and I completely disagree with this but it's also not going to change) there is also a complete ban on *EXPORT* of reptiles too. Even if a foreign country is perfectly happy to legally receive them, Australia will not allow export out of Australia.
Your only legal option would be to get your reptiles legally held by a zoo and open a zoo in Australia and keep them in a public zoo. Even then, while the government *could* approve them import if they wanted to, they most certainly would not allow it for species like Corn Snakes and Common Boas.
If you're interested in studying reptiles and educating people about it, it's ironic that you would have any desire to bring exotic reptiles into Australia. Australia being on the eastern side of the Wallace Line has primitive wildlife and is very vulnerable to invasion by exotic species. Even in the New World there is vulnerability from advanced Old World reptiles as seen in examples like Retics and Burms. Australia is a far more extreme case of vulnerability.
