I'm not sure this expansion warrants stockpiling anything. It is unclear what place professions actually have in gold making going forward other than to provide a few (no more than 3 per character) BOE purples and the very end game item enhancements. I would NOT stockpile profession leveling materials. As a person who has always cared about gold I am anxious about how garrisons are going to gut profession gameplay. I am not playing beta though, maybe it won't be as bad as it seems.