Just a thought about a futuristic idea. Since there are such powerful weapons that can blast holes in concrete wall, perhaps a future evolution is realistic wounds and the introduction of cybernetic replacements. Perhaps its a feature that can be incorporated in a mod or some late idea. If you take so much abuse to a limb, perhaps you should 'retire'/fire a soldier or consider partial or full robocop reconstruction. Sort of fits in with that xcom 2012 mod about replacing healthy limbs with varying technological replacements.
Perhaps when your technology level is really high, then it becomes desirable to simply replace with new stuff. You can use the 'wounding' effects to project how a superior limb will perform in terms of one handed rifle handling, and superior movement bonuses.