I'm looking to use an Armor as Damage Reduction system for my game. I am aware of the variant in Unearthed Arcana, but I'm looking for a system where armor gives only DR and not also an AC bonus. Any ideas on a good scale for the DR (so what DR leather armor gives, what DR full plate gives)? Or how to have magic bonuses (such as on "full plate +2") apply?
My current thought is to have DR range from 1/- (leather armor) to either 4/- (full plate) or 8/- (full plate), or possible have the armor reduction be a range (so leather reduces by 1d2, fullplate by 2d4 or something). I was originally thinking that I could just have the "+1" magic bonus add to the armor's DR, but I'm starting to wonder if that will work. Any suggestions?