An auction house is pretty much a given feature in every MMO coming out nowadays. It is such a convenient mechanic, being able to list and buy anything available in the game at a central location. It is a crucial feature in almost every MMO, and excluding it is almost always foolish. For example, ESO's decision to exclude an AH would have been a terrible idea if it wasn't for the duping exploit. Players struggle to find what they need, due to having to manually spam chat looking for a deal, or list things with high fees to only be available to less than 500 players(in their guild), which likely won't sell at all. A themepark MMO without an AH struggles to strive economically, due to having no reliable means of players exchanging items.
However, I don't feel like an Auction house has a place in Archeage. Because Archeage is a sandbox MMO, it differs from most MMOs recently entering the market. It's core concept is to have player driven mechanics whenever possible; crime/punishment, piracy, castle sieges, and so much more is content dependent on players rather than internal systems. Unlike most themepark MMOs like WoW, ESO, or Wildstar, where the point of the game is to develop static content for players to consume, Archeage relies on the players to be the content.
I feel as if a mixture of player owned shops and manual trading would make the world feel like more of a sandbox, and make the world feel more significant. It would also develop more of a purpose for owning property, as the ability to profit from stocking and advertising your shop could really add meaning to the world. Because you can build on the actual world, and not instanced, this means that player vendors have far more potential than in most modern MMOs. You can open a shop, and actually have it open while offline, not just when using a vending skill. This is a core difference from most MMOs, which is why I feel it will be more successful in Archeage than if attempted in another MMO. I absolutely LOVED vending in another MMO I played, and you even had to stay logged in and idle to vend. Imagine how much better it would be if you can stock your shop every day, and people can buy stuff from you while you're away doing other things.
As a player, it also means you would have to search the land for the best deals. Some may view this as an inconvenience, but in my opinion it develops a more unique economy. Rather than people simply undercutting each other continuously, through a process known as "perfect competition", we start to see elements of a real economy at play. People will shop where is closer to them, at their favorite shops, and seek the best deals. Now there is a reason to go back to that level 10 zone, as you may want to see if anyone is selling what you need for cheaper than your neighbor. In my opinion, an MMO where every single zone is important is the key to success. In every single MMO I've played thus far, non endgame zones end up entirely forgotten, making the game feel much smaller than it really is. By giving these questing zones more of a purpose beyond player housing, every single spot matters, and the game will feel huge.
Now, some may wonder what this means for f2p players. I feel like this will allow for player driven markets. Shop owners may buy items from f2p players, intending to resell it at a higher price(with risk of course). I suppose they may be able to vend locally by their character, rather than a physical shop, too. Manual trade would work as well, so getting rid of items as a free player shouldn't be difficult. I feel like the change shouldn't impact free players too badly(as they cant own land).
I doubt this will change, as it would be a huge difference from the KR version. But if we did decide to change it, it would have to happen before launch. Once players are spoiled with an AH system, there's no taking it away without massive backlash.