The way the auction was implemented is terrible. It's a useless copy/paste of the World of Warcraft auction (when it was back in vanilla with no UI addons) with even less functionality. The posting fee and 10% cut are outrageous and simply discourages people from using the auction and forces them back into the chaotic trade chat.

Instead there should be a Marketplace that uses buy and sell orders. There are only a limited number of items in this game, so the initial screen should have all the items broken down by category. Browse the categories and find the item you are interested in buying/selling. You are taken to a screen that looks like the Crystal Energy market, where you can click a button to buy 1 unit of that item at the lowest sell value, or click to sell an item at its highest buy value. Or you can click the tab at the top and place your own buy/sell order.

If you want a particular item and no one seems to be selling it, you can place a buy order and set your price. This will give potential sellers of that item a baseline price to use, and will also reveal demand for an item. Then if a seller comes along and matches your price, you can purchase the item even if you are logged out. If you log in later and find others have placed higher value buy orders, then you can withdraw your own order and outbid them, or wait for the price to come down.

For weapons and armor with UV's, those are selected as a subcategory under the item. There are only a finite number of possible UV's , so you can list each one separately. This will also reveal if a particular item has a high demand, and will stabilize the baseline price as buyers and sellers post orders that start meeting in the middle.

No listing fee, seller pays 2% of crown cost just like CE.

Benefits of this system:
Already implemented in-game as CE Market, this is just expanding that system to include other items.
Will allow items to reach actual equilibrium price.
Easy to use and understand.
Shows supply and demand at a glance for each item.
Allows anonymous bidding and undercutting, reduces price gouging based on ignorance.

Of course this system would only work if Three Rings undoes this terrible patch, so there's really no point to this suggestion at all.