In short for me, the workload was PRETTY bad. I'm not sure if the workload is the same for both HSC and VCE though.
At the time, I did not enjoy it. But after it all finished, I was like "wow I want to do it again!". It's a bit like a freaky rollercoaster ride which happened too fast for you to understand what happened so you want to go on it again.
Bear in mind that the concept of a "workload" is subjective. Some people may need to take more time than others to understand a particular concept. Some people may also be more easily "freaked out" and hence work more.
Bio workload = non existent. I just paid attention in class and studied the night before the exams rofl.
Physics - I only joined in the last term so I missed all of the assessments/assignments except one. I was lucky because I would have complained about them if I had done Physics earlier. But. The holiday before the last term was not a real holiday for me.
Eco - only had textbook questions for hw although I didn't do them until the teacher was like "I'll be checking your books tomorrow" lol. Since taking up Physics, I never took Eco seriously because I planned to drop it. I spent more effort on the subjects I was going to keep although I did spend hours making notes for the Eco Yearly.
Hey, you do "English, Maths Specialist, Physics, Biology, Chemistry", awesome. I also did Eco and Extension English in Year 11 though.
3Unit Maths was "a pain in the ass" for me at the start because the workload was approx double the previous year's but when I got used to it, it was okay.
Advanced English was approx 1.5 the amount of work than Year 10 (it's like squishing one year into 3 terms).
Extension English was hell because it was approx double the texts I would have to read for Adv. Eng. The independence expected of students was just ridiculous imo. I regretted it as soon as taking it and did not finish reading all my texts, hence theoretically I was screwed to the max for the Yearly. Luckily I was allowed to switch to Physics.
The Chemistry workload was okay despite it being more than Junior Science. I didn't take the first three terms seriously though and did no work back then. Then I was like "shit, I don't know this stuff *studies*"