personally, maths is the only subject i do the h/w allocated by my teacher. for my other subjects,
it depends on how much benefit it provides; sometimes it helps, sometimes it helps. although, i never do the h/w for english - it is literally a joke lol - just practice essays (if you're bothered), or, if you're lazy like me, perfect essays and memorise + adapt them
at the end of the day, as the aforementioned posters have said, it's your hsc. find what method gets you the marks. but imo, doing things like going over syllabus content, reading marker's feedback and doing lots of practice Q's is more optimal as opposed to completing trivial tasks that you'd only do in order to get a sticker from your teacher (lol, only halfsrs)