Yes, an AH will affect the economy, in the same way that wheels affect a vehicle's speed. As in, it doesn't have any without them.
Yes, there will be RMT. The solution is to get rid of them as they pop up, not remove a good system because it could be abused. Murderers and rapists use cars to transport victims and these cars have wheels, the solution is to arrest the murderers and rapists, not to sell cars without wheels.
Yes, people like to bazaar goods. But the notion that people should have to spend hours a day looking for items because of the abysmal lag in the market wards while tabbing through 50-100 retainers selling a hodgepodge of goods at varied prices is an abysmal one. If this game is supposed to be aimed at a playerbase who doesn't have a lot of time to log on, why should the game waste hours of their already short playtime just for them to buy or sell one single item?
Fact: An MMORPG's biggest influx of players is almost always its retail release. Yes, an MMORPG tends to have a lot of bugs at release that need to be worked out, and yes, some people will quit and never come back because of these bugs. That's life. Why wouldn't you want to put your best foot forward though? Why would you want to leave out a feature that is practically mandatory in any MMORPG that has come out in the past 10 years? A feature that, if missing, will drive thousands of players away and scare thousands more from ever trying your game?
I'm not going to make this post about making the game easier or making it intuitive or putting exclamation points over peoples' heads, I'm merely stating a simple fact:
FFXI lives and dies by its auction house. Don't believe me? Ask any FFXI player how many of them use the AH at least daily. Sometimes several times a day. Removing that AH from FFXI would thoroughly cripple the game. It would kill it.
So why shouldn't a feature that is integral to the game's success-nay, its basic functionality-be included?
To be clear: I'm not saying "Hey, you guys really need to think about adding it", I'm not saying "It should be added eventually", I'm saying it -needs- to be added -at launch-.
Afraid of RMT? Ban them. That's what the STF is for. The solution to RMT is not to make your players waste hours trying to buy items. Have you ever considered that since you're making it a chore to buy items, that some of the more impatient players will buy the gil so that they can just purchase the first item they see at whatever price and move on with their life? That decentralized trade will actually result in RMT -thriving- in the game because with the amount of time it takes to make one simple sale or one simple purchase, some less scrupulous players would rather just buy the gil, since earning it and spending it wisely is intentionally being made to be a chore?
Don't sell us a car without wheels just because you're worried it might go somewhere. We -want- it to go somewhere. That's the whole reason we're buying the car.
Please implement an Auction House -at launch-.