Maybe the point is that you haven't provided enough info to allow for a good recommendation as there are literally dozens of different RTW fare products which might be suitable for that routing (your assumption that there are only 1 or 2 is not correct). The available products differ a lot, and which is best depends on your objective -- none of which were stated in the post: class, cost, FF mileage accrual, FF status accrual, maximize or minimize mileage, add extra travel to reduce cost/mile. The "best" fare can vary from AUD 2500 to AUD 10000 depending on these objectives. Some are cheaper in Australia than in Hong Kong, some are not. So there is a lot of variation and room for optimization.