Motors and Generators was quite a challenging though interesting and rewarding module for me.
Space was just bleh...space.
I2I was quite easy to understand but I was prone to losing silly marks in it.
Age of Silicon was ten times easier than I thought. I remember someone telling me on this forum not to do it if I did not have a computer background but using the Jacaranda chapter it was the easiest module and was equivalent of difficulty as year 11 "electrical energy in the home" module to me.
In terms of options, you need to be interested in history and elementary particles for q2q (or you can just rote learn), I can't really say much else for others because I have no idea what those options are like.