I'd like to suggest that by paying an additional flat fee, players be allowed to set up an auction as a "featured auction" item.

This fee would not be returned if the item sells, and the item would be marked as a "featured player auction", which would go directly underneath the normal featured auctions, and would have a new colour to suggest that it is such a thing. There would be a maximum number of player featured auction slots (around 25), and they would be first come first serve.

Another thought is to have the slots cost a different number of crowns each.

1st slot: 5K
2nd slot: 15K
3rd slot: 25K
etc.

Though it shouldn't be neccessary.