While I don't agree with OP, a gold sink for those with 1Mil+ gold would be awesome. We have the market, now, but there really is no point in amassing more than 15-30 heirloom points. What I would like to see is unique items.
There could be like a lottery, where you can buy tickets, and the amount of tickets you have is equal to the chance of winning. Similar to lottery loerdag, but with ingame gold instead of real donations. Each week/fortnight/month, a winner would get a free pass to make one of his items unique. Only masterwork items could be made unique, and they would gain an additional stat bonus. Additionally, the player could name them, and when he would join a server, a notice would display like for the owning of fiefs, announcing him as the owner of <TheNameThePlayerChoseForTheItem>.
Now what really would make these items special would be that there could only be 1 unique item of each type. The first one who made his pitchfork unique would forever be the owner of the only unique and named pitchfork (unless he chose to trade it, of course).
Maybe in a later step, these items could also gain a unique model + texture.
Another idea for a gold sink would be a buyable heirloom respec, allowing to free heirloom points of items for 100k gold.
Or of course, like other games do it, introduce consumables, that is, items which after use must be bought again, like the firebomb. If they are expensive enough, they won't be used excessively and could add some spice to the game. The only problem is finding fitting items, as I feel potions would not really match with cRPGs setting. Maybe battle drugs? Or make throwing items and arrows consumables
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