Sorry, I should make it clearer. I used the word extreme to designate hilly. In the context of the original poster it's pretty clear:
From the OP: I'm planning to compete in a 75km race with 4 1000 meter vertical assents in October. This is about as mountainous as you can get in Australia. This is a walk in the part compared to the races in Europe, New Zealand and North America.... I look at the course profile for that, and the course profile for the 4 1000m assents for the 75km race I'm doing in October
The whole point is that you don't need high altitude to get extreme elevation change in a race. I'm more familiar with cycling, but in that sport there are probably only about 4 or 5 rides in the world we can't match in terms of hill climbing, and those are either extremely long continuous climbs (eg, Haleakala, Alto de Letras; our longest is 30km) or 10km+ at extreme gradients (over 10%; Mount Zoncolan, Alto de L'Angliru; out longest is around 9km).
Generally you can make the race harder by looping it over steep terrain, just like the Barkley does.
I was hoping the OP could enlighten me as to why we don't have trail runs in Australia that are just as challenging.
