Old timer said:
...So far most weapons (guns) can cause impale, chose location and bypass armour, and i am thinking sunder might be an option as well...
...Of course if you want keep it more realistic, then no evades v fire arms, and make more use of cover...
...Armour provides x protection, but if a bullet fails to penetrate, target still takes a point of damage from the impact...
A few tidbits, some opinions, some not. Mind you, I'm not being trying to be derogatory, just informative.
Don't do the 'bypass' armor thing. Otherwise there is no reason to have armor, or weapons that aren't guns.
As to the always does some damage, first, you are adding another layer of things to be taken into account and dealt with.
Second, it won't, armor is both padded, and designed to distribute the blow.
Besides that, the energy calculations on a shot from a .38 is about the same as that from a strong piercing blow from a dagger or the like. There are people that study this stuff. What you have to watch out for is myth, Hollywood, and over-estimation of modern devices and techniques. The sheer damage our modern guns do isn't that much different from ancient weapons. The differences are accuracy, range, weight, and ease of use. And shooting someone with a gun doesn't knock them off their feet, with or without armor. (Mind we aren't talking about artillery.)
Evading bullets. Let's start with the obvious, you can't. I doubt you could evade an arrow, or at bar-room ranges, even a thrown dagger. But this is action genre, so you can. It's the same with bullets. In truth, since you can't really dodge the projectile, or an attack you don't know about, what you are really dodging is the aim of the attacker. (As to evading traps, sometimes you move because of the subtle click, not the poison darts.)
Duck and weave baby, duck - and - weave.
Making it more realistic. Mmmm... Maybe to a certain extent, but then again, you're probably going for some kind of action adventure. Besides, if you wanted it really real, you'd double the all the weapon damages and increase wound penalties. Real combat is rather messy, and one or two decent hits tend to incapacitate or kill most people. You don't get much adventuring done in those conditions unless it's the social/political games with hardly any combat, if at all.
Now there are some very rare people that can take horrible damage and keep functioning with limited impairment for a short time. Usually no more than 5 or 10 minutes tops. Then they succumb and are just as useless as someone that doesn't have that extreme response. I know a person that had multiple fingers on one hand chopped off (through the bones), and the muscles and veins in his leg severed. The scar on is leg is about a foot across. He pulled the object out of his leg, applied pressure to both his hand an leg to reduce bleeding, and walked to a safe area to wait for help to arrive. Most people would have been unconscious within a few seconds. By the time the ambulance arrived, he couldn't sit up. It was 2 months before he could walk across the room with only a cane.
Now are you sure you want the damage more gritty and realistic?