I don't know about the majority of you but, I make most of my money off of the Auction House and I think that being forced to pay $1 for an extra 7 AH slots is a bit harsh. Most MMO's today don't even limit the number the items that you can place on the AH house and the one's that do usually have pretty steep limits closer to 20 or so.
Also, I think it needs to be taken out of the dark ages. I think that instead of just putting up an item and waiting for someone to buy it, I think you should be able to put up buy orders. Similar to how you can buy stuff in FFXIV's bazaar system or at least how it was the week I played FFXIV. This would be a boon to crafters that could just set up a buy order for how many of an item they need and just tweek the going price every day or so.
And lastly, I think that whole having to take an order down to change anything about it is a bit out-dated too. Why can't I just go into a little screen and adjust the price and pay a little extra tax for it? I mean these are features that a standard in a lot of MMO's but due to FFXI's age seem to be overlooked. I know that there's more dire, "balancing" issues at hand but I think ease and accessibilty in the Auction House isn't too much to ask for.