So I think we should be able to post our excess materials on a type of market, but differ from other auction houses: have the buyers control the prices more. I think if there were a page that had a " Wanting to buy " feature sellers and buyers alike could get what they need and not spam endlessly in trade. It could work in different ways, obviously a huge list to just look through may take much too long to through but to have each recipe have a button that creates the tickets for you, it would be much easier. Say you need 1 iron gear you just click " Post for missing materials on market " and go through each material you want.

Another feature of this would be posting how much you are willing to pay for said item, and have the sellers click a "Fulfill this order " type of button. Willing to pays could be be paid out in energy, or crowns, and would be automatically taken out of the players stash of payment once the order is fullfilled. I believe having an average amount of crowns paid for each item posted for each "Wanting to buy" would help each player know what things are going for, but be able to offer lower if they are not in desperate need, or higher if they just want it now.

I know it sounds almost just like an auction house but this way there is not an auction house full of things that are not going to sell, not all mats are needed at all times, and some players may or may not know that their materials are not going to sell, if they could see the demand for each item, say iron gear had 300 requests under it, they would know what to look for better. Wasting hours a day spamming about a material that isn't used in popular recipes is just too much spam and waste of time, automate it and it makes everything better for the player.

As far as the rest of the details go, I have not thought of each but I do think an auction house type market based on players wants, rather than players desire to hoard mass amounts on an auction house makes this more unique than others, and because the buyers control the prices, no jerk can randomly start selling t5 materials for 1000 gold. It's happened on other games where bots can farm mats and sell all they want, in this scenario it is more buyer driven and not as easy to change how much something is worth to the rest of the players.

edit- I figure another feature added could be looking up " Wanting to buy(s)" based on the materials you have as well, so you're not looking through endless lists of things you don't have, but can see what people think what you do have is worth.