Yes, actually, IPs have apparently just started to be marked, so yes you definately still have a chance. There is this guy in my class who is absolutely SUPERB. He did "Rhinos" a piece from an Absurdist place. He was brilliant and received 30/30 for his trial. Not too good at theory, very lazy with theory, so I was hoping he would get nominated just to give him recognition that wont turn up in his marks unfortunately. But apparently they nominate on average one piece at most per school, so that is the only reason i can think of. Personally, I think his monologue is perfect Onstage material, and much better than some of the garbage you see there.
We only got 1 nomination from the performances and that was our group. In answer to your question, we did a narrative piece about 4 missionaries (all guys group) who sail to an island in search for "the light". Its a comedy, pretty 'stupid' comedy, sorta pokes fun at blind faith, but we tried to keep it as simple as possible, not making too much of a statement. I find that comedy works best for HSC Group performances, and that what we aimed for. Its fast paced as well. So for future HSC students, I say go for comedy and aim for originality.