Uhh, Moon, most of what you posted is wrong.
Scaling doesn't depend
at all on "the quality of the paper set".
Not sure whether you mean 2001 or 2002 by 'last year', but either way, in both years, aligned HSC marks of 40.2 and 31.9 placed students at the 25th percentile, so obviously the 'minimum mark' would have been much lower than that (and such details are never released - nor are raw marks).
In both 2001 and 2002, the overall academic ability of the History Extension candidature was considered to be above average, and so it was actually scaled quite well, not "terribly".
Similarly, Economics was also scaled well in both years, although not quite as well as History Extension.
Legal Studies and SDD weren't "scaled wonderfully" for either year - they had only average scaling in both 2001 and 2002.
The proportion of students achieving aligned HSC marks in band 6 in a particular course has no bearing whatsoever on how that (or any) course is scaled, and will have no effect on the resulting UAIs of the students who took that course.
Whilst theoretically the scaling is
liable to change every year, the statistics released which pertain to the 2002 HSC are extremely consistent with those from 2001. Nearly all courses were scaled the same - the ones that differed greatly were LOTE courses with very small candidature sizes.
Having said that - doing the subjects that you are best in is definitely good advice.