I really liked /market before the reset, it was a place where players could rent a room and make a custom shop with sellchests. if that could be added back, that would be cool.
/market? I thought it was /warp shop. But, yeah, this would be cool. Although, there would need to be a rule that you MUST put a shop in there; about 75% of people just used it as a storage room, which cluttered it up. Maybe add a /playershops menu, where you could view the owners of each shop? Maybe also /playershops search, to search for a players shop? Then you could instantly warp to a certain shop. Also, unclaimed shops would be shown with a Barrier block, so you know if there's a shop up for sale.
Having player warps and sell chest I feel eliminates the purpose of implementing this so I will be denying this suggestion.