So Power Attack?
It could work.
I've been toying with the idea of changing weapons myself. I've been toying with the idea of RQ6 style flat armor (but without hit locations) and more importantly, removing damage rolls. My thought was that for every 5% you succeeded by, you add damage to your attack, depending on your weapon, and all weapons do 1+amount based on the attack roll. So if someone rolls well enough, they can kill a man in plate armor with a punch. Currently my idea involves a table, so that a greatsword will do more damage, faster. It's hardly a fleshed out idea, and you would have to Iron out the kinks/refine it, but you might be able to do something with it.