PermaDrain I am not sure we are on the same line here.
Days to re-order wants from you the number of days you need to get the new stock in so you never run out.
Stock Central will mark the product that is about to run out as LOW STOCK so you can place the order with your manufacturer in time.
WooCommerce already offers you to enter the value per product - yes that value is not yet shown in SC, but we do have this on the list of many SC improvements that we want to introduce in 2020.
Does this work for you?