I'm not from South Australia, (WA instead), but I'm sure its basically the same type of system.
First of all, it is possible to get a TER of 95 with any combination of subjects. For us to assess your scaling though, you'd need to post your subjects. Wherever you live, its pretty safe to assume that subjects like Physics and Chemistry will generally be weighted higher than Art, for example.
However, the affect of scaling is lessened by performing higher in the subject. I do Human Biology, which is generally a subject which scales downwards (but not always). My teacher explained to me that since the majority of students achieve a raw mark of between 50-65, these students are the most harshly affected by scaling. However, those who achieved higher marks (85+), were generally not affected by scaling.
I know this isn't very clear, but my message is that no matter what subjects that you do, you can still achieve any rank, provided that you work hard enough for it. Also, don't choose subjects just because they are higher scaling than others. Thats one recipe for disaster, in my opinion.