TL;DR If you want to go into medicine;
1. take chemistry, and advanced math or higher
2. sit the UCAT
3. apply for early entry into the "Bachelors of Medicine/Bachelor of Surgery" (MBBS) at JCU and Curtin
4. if you don't get in, apply for regular UAC entry into any MBBS
5. if you don't get in...
If you're interested in sci ext, it is very easy for schools to run with only one student, it's worth pestering the science faculty if you think you'd actually want to do it. Otherwise though;
14 units is a lot, especially since you'll have the option of picking up extensions if you need units...
I honestly have no idea if you'll get an 80 (just bc I don't know about your specific subjects/your high school) but lets just say that you don't;
UNSW has just lost 25.1% of their students bc of covid, so their 80 entry score for arts (assumed based on your subjects) will almost definitely go...
A lot of unis are starting to require advanced math (I know usyd and anu definitely are, I'm not sure who else, but I can guarantee that more will follow by the time you graduate), it'd also might help you with econ (I haven't taken it so I'm not totally sure, but it wouldn't hurt)
But other...
heres my method;
1. go to google scholar and search the name of each of your texts (individually)
2. find some interesting papers academics have written on it that are at least tangentially related to the module
3. take notes of their analysis
4. use that to inspire your own analysis, don't...
Don't worry about subjects scaling well, if you like it, you'll study better, and you'll do better than you would in a subject you don't like that "scales better".
For people who are good at/enjoy english, 3u is significantly easier and more interesting than advanced. It can conceptually dense...