5.Ranged damage based on skill.It would make sense for maybe unarmed,but if i shoot you with a gun it isn't going to hurt more/less whether i know how to use it or not.
I'd agree with most of your list, save for this one.
This isn't a terribly new concept, and I've played a couple tabletop rulesets where damage was modified by your degree of success, for example. (Rolling well under the to-hit chance would do more damage than the same shot just barely making the roll.) Essentially a character with a higher skill level would have a better chance of success and be able to do more damage than a novice marksman - works out to basically the same thing in Fallout 3, where skill level is more of "spread" effect than a to-hit roll.
Because not all shots are equal, mind you. Let's say I'm an excellent marksman, I'm going to be much more likely to be "dead on" with my shots than a novice. I will be more on target, and the chance of me landing a glancing blow is much smaller than someone with lower skill levels. I know where all the "sweet spots" are and will be aiming for those, and be much more likely to hit the right places. A novice marksman is going to be more worried about simply hitting the target at all (even if you're going for a head shot, or a limb wound, etc - you're more worried about hitting the target than about placing a bullet between the eyes, right into a nerve cluster, severing an artery, etc.) Which means more grazing shots, near-misses, flesh wounds, etc.
Yes, getting shot by a bullet is going to hurt regardless, but not all shots are created equal. A bullet that hits me right between the eyes is very likely going to kill me right out. But if that same bullet simply grazes my ear or glances off my skull, it's going to have a different effect (losing less hit points.) This is what the system is meant to represent - higher skill levels means you're making that shot between the eyes, while at lower skill levels you're more likely to make that grazing shot.
It doesn't have to mean that somehow the bullet is leaving the barrel of the gun at a different velocity depending on your skill level.
Now, for the sake of realism damage caused should be a range that's modified by your character skill. So that a novice character still has a chance of making that lucky shot. But I think that's what critical hits are supposed to account for anyway.