I'll have to dig out my copy of Phoenix Command someday.
I think there's something to hydrostatic shock--if you see how much it displaces and disrupts organs I can definitely see it knocking a person out or even sending them into actual shock. But in Hero terms that would be more like +STUNx than added damage. I think rifle rounds probably do inflict more damage against bone than handgun rounds would, though I'm much less certain of that.
I've taken a couple of abortive stabs at modeling different types of damage and armor in FH. Mail works best against cutting attacks, padding works best against blunt attacks, plate is best for piercing. But it tended to run aground on the simplicity of the DEF/BODY mechanic for inanimate objects--I was going to have to define (at least) three different DEFs for every object type, so forget it.
Still, you can see this play out in the evolution of European weapon use through the Middle Ages. Swords were straight-bladed for much of their early existence, reasonably useful against both unarmored peasants and barbarians in mail or brigandine. Then as armor got heavier, so did swords for a bit, until the armor just got ridiculous and the sword was relegated to ceremonial or backup status while the weapon of the day became the pike or polearm. Then as firearms caused the phasing out of armor altogether, the sword became a mostly-slashing weapon, used with devastating effect at Waterloo* before finally fading into obsolescence.
*By the English; the French cavalry sword at Waterloo was still a stabbing weapon.