"Edit in Excel" is a wonderful tool. Unfortunately, it sometimes seems like a developer used the dart board approach when deciding which fields to make editable.
Aside from "Item no." and "Description", "Unit_Price" is probably the most crucial field to have available for update in the "Edit in Excel" capacity. When a company increases its prices, it normally does so either universally, or for a selected group of items. In either event, you are basically considering a mass update. Quite often this takes the form of a "5 % update", "10 % update", etc. This is the perfect situation to be addressed in Excel.
While I understand you would have to validate the decimal when validating during the "Publishing" process, exposing the "Unit_Price" field is probably the most useful change you could possibly make to the "Edit in Excel" function within the "Items List" screen.