If possible I'd recommend reworking the inventory, storage, and shop interfaces before too many stores and such are added. The amount of items already in game is impressive, but managing depositing/selling/using items is a mess.
Selling a full stack of items. Inspecting an item so you know what it does would be nice. And using more then one at a time would be nice.
Just something to think about, better to get core systems ironed out ASAP in my (limited) experience so a rework later is not hellish. Goodluck.