Sup there!
Here's some my humble suggestion about the trading system. I'd like to have a possibility to trade all the items I can find in the game - weapons, armors, literally anything the enemies drop on death. This was the most painful experience for me when switched from the original Guild Wars to Guild Wars 2 where a half of the loot you get is account/character bounded and impossible to sell. P2P trading would be another feature nice to see. A marketplace itself is not a bad thing, but a P2P trading is another way to make people interact with each other, and MMOs are all about that, right? ;)
Hope, you guys at least think about that and maybe, just maybe we'll see all these stuff in a final relase. Cheers!