So.... as stated elsewhere, here's my ideas.
Let's call a spade a spade. Whatever fixes you come up with... Glitch doesn't have "Auctions" it has a player-driven "Market".
Building from there...
Perhaps we only start out with a certain amount of 'space' in the warehouse. Thinking in terms of bag slots, perhaps it's 10 to start out with. As we grow we can expand our space in the warehouse...
Several options for methods of expansion here: Building permits, currants, or maybe linking it to a new 'trading' type skill. I'm hesitant to throw it out there, but an extra 5 starting slots *could* be a subscription advantage, but because it *will* provide a slight (but optional) advantage - I'm strongly against purchase a-la-carte. It translates directly into real-world cash providing a significant advantage when such a feature is offered on an unlimited basis.
Each slot would hold the same amount a backpack slot would. If that means 5 gems, 3 stacks of meat, and 2 stacks of grain... then that's what you can auction off. If that means you have 355 auctions listed because you sold each one off one at a time (5 + 150 + 200), good for you.... but you won't be able to auction more until one of those 'slots' empties.
I think the concept puts a nice, flexible balance on things. If you're putting up stuff at prices people want to see, you'll have more room to auction right away. If you're auctioning debris or using the market as a storage container... well it discourages that type of use.
As an add-on... perhaps the 'storage' appears on your Inventory line, a 17th space if you will. Dragging an item into that spot brings up the auction interface (preferably with some sort of cool indication of how the rest of your auctions are doing).
In the end, I trust the development team to do right by us when they go through and fix things. I like my idea, but will settle for the name change to Market.