They are really impressive rankings unless you go to a hopeless school but that doesn't matter too much even if you do and if as you say you are going to improve your SOR ranking thats even better. Congratulations on Hist Ext. too
...Our school wouldn't run it until we got the 6 in our class [also: more people do art than 2u Maths?]
I guess you mean HSC exam mark of 90+ with band 6 (even though bands aren't determined exactly like this)(1st in Eng. Adv. and expecting 90+ is very desirable) and if so you will definately get your aim of "atleast 85" and its possibly to get mid 90s and higher but of course it is all about what marks you get in that exam.....try SAM or JUAI perhaps
What do I base all this on?...what I've read and my conversation with the regional BOS person...nothing more
[Edit: Spelling]