I have been reading that many people have kind of gotten board once they reach 50 or beat all the quests and the only thing left is crafting. I don't know if this has been suggested already, but I havent seen it around.
Along the same lines of owning a house or castle, let players open shops to sell their creations. There could even be bonuses for specializing in a certian area like cards, hats, athames, etc. It gives the shop owners plenty to keep busy finding the resources and make gold at the same time. It also would allow people another choice like the bazar.