Since Dual Spec has become popular I think there should be armor for different classes. Like some that require str and dex for example a level 50 (60) armor that requires 125 str and 125 dex and has points on both this can be used by birds and warriors alike and a set that has str and int requirements for paladins and so on. This sets can be specialized for this classes but there should also be other sets for pures.