Why not simply buff all armor then? Light armors are practically useless because you die in one hit anyway. Might as well save yourself the encumbrance and run around naked. Alternatively, here's a better idea: tweak damage types so that cutting damage drops much faster with armor values. The reason why 2h heroes love their e-peen extension swords is that they can just spam and look cool, and it works. Cutting weapons should only be a viable choice against very light armor, damage should drastically drop around the point where armors get mail. Combat is fast because agiwhores run around with 2h swords, which are too fast to begin with imo. Another thing, but much harder to do is poise, kinda like in Dark Souls. The more poise you have, the harder hits you can take without staggering you and without interrupting your attacks.
