Aside from other issues i have with the market place (Restrictions and stuff) i feel like the UI for the market place could be improved.
Instead of when searching for an item it comes up with every item that is being sold that fits the description, how about it just lists the type of item that fits the description (so like instead of showing 20 swords all from different sellers just have it shown once)
Then when you click on the item that you want it will then list all of the sales going from lowest to highest, i feel like this helps divide some items that look really similar and makes it easier to search through the marketplace.