It’s already in place for cultural weapons. Especially when the karma vendors in Orr temples don’t always offer the stat spread you’d want for all the builds. I for one had to buy every single piece of my exotic gear off the trading post as Healing, Vitality, Condition Damage isn’t anywhere but it’s the perfect spread for my Support Necromancer.
I guess it’d be better if karma was shared account-wide but that would create problems too. Now I have this karma I don’t know what to do squat with. I don’t need a damage focused set as whenever I get that itch, I have sPvP anyway and my Warrior to play, I like my spec for group dungeons and WvW enough to not need another set.