The problem with need/greed is that it only really works if you only have one job leveled. If the game prevents you from "need"ing an item for MRD, which is your main, because you're on THM because it's useful in the fight you're doing, for example, that'd also be pretty suboptimal.

Definitely suggest at -least- a quartermaster system, or make Ifrit drops behave like other drops in the system until 2.0 comes out (less optimal), or auto-drop items to people's inventories that can then be traded in for an Ifrit weapon of the person's choice.