Regarding recipes, what you're saying makes sense, at face value. However, there is currently no example of recipes being flagged with pre-requisites. The only way I could possibly see what you're describing working without adding a new system to the game, is for them to make it a repeatable quest, and require you to use the "craft item for quests" button to make the gear. Which would be seriously shoehorning a system that wasn't intended in.
It wouldn't take some complex system. Do a one-time quest or even just buy the recipe with seals that changes an if statement from no to yes then you can do the recipe at will.