Personally, I'm a huge fan of gold sinks, I wish they'd do more of them. The problem is there's way more gold coming in than out...which causes a deflation in the cost of gold, so all your items will drop in value and if you sell gold that'll hurt you. This will eliminate more methods for bots, thus that'll reduce a little gold coming in the game, especially with higher skill requirements. A lot of accounts will be banned before they can even get to certain methods, so that's good(economy wise). I definitely wish they'd add more gold sinks though. I really love the tentacle whip, that's a great example of a gold sink. Of course there's the gate fee, some construction, converting bonds, repairing armor, etc... They completely remove the gold from the game. More gold being removed and less gold coming in = more inflation. I'd love for them to make something else for the non-degradable popular stuff like bandos, fighter torso, abyssal whip, defenders, void and dragon scimitar. Many people use them that way they don't have to spend money to repair them. Some people don't use barrows and use non-degradable just for that reason. It's very late in the game now to do anything like that, as it would completely upset the community and everyone would be upset, but it would be a nice idea. I think making degrade to dust armor, like malevolent on rs3, is also a great idea.
Also, they locked a lot of it behind quests. I'm sure Token could make a pretty penny if he added those quests to his script.