Recently there's being a huge increase in the number of new costumes/accessories. I'm not here to discuss the motivations behind it, but bring up some potential issues:

There is no "sink" for cosmetic items
Players have no incentive to remove old costumes/accessories from the game. They just get recycled into the market. As new ones come out, demand for old ones decrease. Accessories that once served as crown sinks become everyday trifles This can only get worse as more and more are introduced.
Look at the prismatic bolted vee and hallow costumes. That's basically an accelerated version of what is happening to various other accessories.

Prize boxes are no longer anything special
Currently there's a gremlin event. I don't care, because I'm betting in a couple weeks there will be a new fad. Why waste money on this one if it's going to be replaced so soon? Granted not everybody has this mentality, but I think it will hurt in-game purchases overall. It used to be that a prize box event will drive energy prices down quickly. Now they are so common, there's less "pressure" on the market.

Promoting consumerism
There are already people who manipulate the energy market for profit. There's now an increasing number of people who are depending on the cosmetic market for profit. Players should be encouraged to get money by exploring the clockworks, not sitting around haven watching the Auction House. The typical day for some knights consist of the following:
1. Look for good deals.
2. Sell purchased items for more money.
3. If there's a new event, buy tons of the new stuff.
4. Return to step 1.