If you're relatively sure about what subject you want to drop, pick an easier subject (to fill the units). Essentially, you have less things to deal with (- stress); and can focus more on subjects like 3u maths (+ y12 marks).
Ext 1 Maths
PDHPE
English Advanced
Chem
Business
and im thinking of like eco or something?
what do you guys think of the workload for all these subjects?? im pretty good in humanities