Australia is honestly not that dangerous. There is practically no chance of getting killed by an animal in the bush if you think ahead (as opposed to places with things like bears, moose, bulls, lions, hippo, rhinos, etc.). All the large animals are non-confrontational, so unless you do something like try and steal a baby emu or hug a wombat you'll be right.
The only real danger is snakes, but if you watch where you're walking and make enough noise, you probably won't get into any trouble, and even if you do, if you wear long pants and/or gaiters you should be safe from their venom.
The ocean on the other hand is full of things that can do some serious damage but most of that bollocks is further up the coast from me anyway.