In this Shop chest is some white wool. Imagine, though, that it were filled with multiple dubs of different-colored wools, making it hard for the buyer to find what they're looking for.
As another example, and as one I would personally find more useful, Void Storage chests often contains several dubs of many different items. There is a way to go directly to a certain type of item (Shift-click VS frame, click on the item you want), but that's not incredibly obvious to players.
What could solve these problems with a nice simple UI update? A search bar!
Here's an example.
Upon searching up the item you want to find - let's say red wool - you would be presented with only that item, making it easy to find what you want.
EDIT: This could also help with the current enchantment issue for VS!