Similar to the Legion vendor in Dalaran, would it be overly difficult to implement a vendor that allows you to trade expulsom, tidalcore, etc. for crafting materials? Profession resources such as zin’anthid have absolutely skyrocketed across servers, causing potions and flasks to become prohibitive to much of the player base.
Another idea that could also resolve this conundrum would be to put zin’anthid and osmenite nodes in the new Uldum and Vale of Eternal Blossoms, allowing players to farm said nodes at the same time as they are completing their dailies. These zones are also far more populated, which means there is a greater number of shards of said zones (combating the multibox armies that are plaguing the reduced number of Nazjatar shards).