Over in the land of Blizzard twitter, Senior Game Designer Jonathan LeCraft has confirmed something that should make crafting and various Mists of Pandaria-era projects far easier for players: in patch 6.0, Spirits of Harmony will become unbound.
@mfgIcarlos Yes, it will be unbound with the expansion.- Jonathan LeCraft (@TheCrafticus) June 4, 2014
While I personally would loved to have seen this happen in 5.4, late is better than never. This way, folks will be able to buy, sell, trade, and store Spirits on whatever toon they like. Though most of the things we currently use Spirits of Harmony for will almost certainly become obsolete in the new expansion, their being unbound will make collecting legacy recipes or completing old quests (such as the Pandaren Cooking Ways) much simpler for future alts and players.