I think that the higher the slider is, the more likely it will trigger the animations that create the penalty (or the "feel" of the penalty, with regard to Madden)...
Higher will make the DL "ignore" the possibility of roughing the passer and they will go all out...
Low and they SHOULD be less aggressive...
I think that to minimize sacks:
Offsides : Below Default
False Start: Above
Holding: Above
IG: Above
RTP: Below