Firstly, it depends on the weight of the assessment task. If it says 20% on the assessment sheet for example, then it will be worth 10% of your HSC mark (HSC Weight = Internal Weight/2). As for if you should drop Ext 1, it really depends on if you think you like the content and will endeavour to...
im doing the same, I literally cannot find a related text that someone hasn't done in past years at my school (therefore 'no originality' in my teachers words) 😭
rn, modern is so good, 4u is amazing, physics is good, chem is kinda mid/kinda interesting (in the middle), and legal is a bit boring, yet interesting as well.