Dark age of Camelot had a similar armor system to the one you are describing. For instance, plate was weak to crush (blunt) strong to cut, and neutral to pierce, Chain was strong to cut, neutral to blunt, weak to pierce, and leather was strong to blunt, weak to cut, and neutral to thrust. And it was nice to make weapon decisions based on what you were likely to face.
Something like that would be fun and refreshing. Probably a bitch to code though.