In XI a friend of mine really wanted an armor for his dragoon, but it was very expensive. He spent months getting the materials to make it instead of buying the mats or the armor itself on the auction house. He began the quest months before reaching the level where he could wear it. The moment the crafter made it was very suspensfull for him too. The epic nature of his quest to get this item really added to his enjoyment of having it. It was a level 70 item and he still keeps it at 90 even though its no longer useful.
I think there should be similar items that are gotten by finding all of the parts needed, and then having the final item crafted. This should also be a player crafter, and not an NPC like with +1 Relic and Artifact armor. Perhaps like with synergy items in XI there would be NM drops needed along with items aquired through quests. Optionally this might require making it possible for a person to add rare ex items to the materials list in a crafters pool, and having an untradable item given to the person who is requesting the craft, and not the crafter. The journey itself should be epic in nature, and the item returned should be equal to the effort involved. It should be something that a player should be able to begin questing for before the item is needed.