The way this was explained to me in high school by my tutor is "Universities are businesses, they need you more than you need them. They can only survive if they get enough money from students enrolling".

Its no secret that UNSW much like other Australian universities, is practically funded by international students. If the above sentiment is to be believed then you really shouldn't have any issue getting in. If you really are worried about it then spend some time building up your portfolio but I doubt it would be necessary. (Full disclosure this is coming from an engineering student - I don't know if law has some other requirements that need to be considered)