How about we get fragment pieces of the 50K AP specialize gear that the town vendors sell? These pieces should be transferable/tradeable/sellable. And when we collect 50 pieces of any specific one, we can craft any armor piece of that set in any trait that we choose provided it's a matter crafter.
A random assortment of raw materials -- whether just alchemy or for all crafts -- would actually be pretty interesting. I imagine the set pieces as being a more "immersive" reward for being good at combat (or standing in a zerg) but at this point yeah I have all the pieces from those sets that I could ever need, and if not I can generally pick one up for less than 2k gold at the nearest guild trader.
Tri-faction tryhard but mainly EP in Gray Host lately (PC/NA)