I wouldn't mind seeing the auction house become more used. You cant buy and sell gold there. you cant trade EC there. Cant trade you custom armors there. Can't even trade the custom materials to make items. It's kinda like a part of the game is missing. The only thing notable in the AH is skill books.
I remember when i first started learning pwi's AH it was like a whole world of opportunities opened up for me.
might make less catshops which would cut down on afk server usage.
make farming a more universal form of income no matter what your farming.
less people on world chat buying and selling.
lets people compare prices on items at a glance instead of checking 3-4-5-6-7 how ever many catshops to see values.
the transaction fee's
coding or what not. time required to actually do it.
anyway wouldnt mind hearnig what others think on the matter