Through years 9-10 i did commerce, computer studies and visual design. Computer studies and visual design was the biggest bludge i have ever seen. Commerce actually required to do some work. But heh when you think about it all of your junior years are a big bludge.
A long time ago back in year 9 and 10 I did Technics Wood and Japanese. Back then Computer Studies was a compulsory subject atleast at our school (is it an elective now?).
I also did Commerce and computer studies back in year 9 and 10. Commerece is definitely a subject worth doing, as it prepares you well for any social science you're thinking of doing for the HSC, namely economics business studies and legal studies.