Now this may or may not have already been suggested, however I think this would be a good idea to look into. The higher level players want a gold sink because from what i hear, the amount of gold you get versus how much you spend is high.
Think about a customizable house that is player specific, and you could invite a bunch of friends over for a house party. (this could mean player organized christmas and halloween parties etc.)
It could give a gold sink for the higher players because they would need to buy some stuff for their house, or put money into crafters to make stuff.
you could sell house/manor items in the eldevin market for ep/lp/pp
it would give wood a use besides making weapons or firewood.
all you need to do to fit it into the game is say its something like the alphex void.
you could give the house/manor stuff like a pvp arena or something like that
once clans/guilds come out you could make it so that each clan gets their own house/manor
houses/manors could be rested xp areas.
you could add things like crafting stations to houses.
you could do so many more things with this idea
I would really like to see this implemented into the game, it would make it lots more fun!