I think you should try to do your course at UNSW or USyd. Most of the courses you are looking at are near-identical at both UNSW and USyd from what I've heard, and USyd and UNSW are both high quality universities for arts, law, etc.
So it really just depends on what you personal preference is for university. Consider social aspects, post-graduation opportunities and travel time to choose between UNSW and USyd.
Also congrats on being able to choose between great universities.
I'm looking to do combined law, but I'm only able to do it at UNSW. I'm also trying to decide between arts, communication, media, etc.
Anyway, good luck with your decision.