To everyone who I've said potentially could have subject bonuses from The University of Melbourne, my sincerest apologies for misleading you all. Apparently they've changed things since what I remember in 2014, meaning that subject bonuses are unlikely a thing at The University of Melbourne any more. I've only recently discovered this myself in
this thread. Sorry again.
Regardless, I would advise that your first preference should still remain as what you wanted most, as this gives you the chance to still get in and is much better than leaving it off your preferences entirely (giving you absolutely zero chance).
Is going to Uni for music a good idea?
If you really enjoy it and/ or want to pursue a career in music, why not?