Sorry I'm way late with this, but any answer's better than nothing, right?
Lowering your HP/MP count shouldn't be too hard, just go into those stats and set the minimum as like 50, and the maximum as 999, then set the curve between those points.
As far as that experience lingo goes, I don't really remember exactly what each does (sorry...). All I remember is that the tertiary is roughly how wide the gap is between levels (low tertiary = almost no difference going from one level to the next). My best advice would just be to start with low values on all three, then mess with them a little 'till you get something you like.