Since in the world of Xsyon, players or Tribes will be mostly be trading Materials, Raw Resources, Items, etc ( as i believe there is no currency in the game )
what about a Player owned Stall like in FFXI Bazaar, so you can build your own Stall, put your items there, and you set a trading item of which you want for the certain item, i think it would be a good idea for a Trading Hub
also, other players from other Tribes, or a traveling strangers could just put up a list of what he wants for a trade in some sort of a Message board, and the owner can list the item and get back to the players, i think this will be a good feature, not only it will save your time but also, you can even create a Market Place in the game, all run by the players, which is pretty awesome!
i haven't seen that in any MMO since player Bazaar in FFXI
has there been a talk about this yet?