I think the number one most missed thing by WordPress developers is properly thinking through and setting up Shipping Zones and Classes. It can be a bit of a headache, unless your store is simply including the price of shipping in each item, and touting "free shipping!"  Maybe this is why it's often "forgotten."  However, a solid alternative, especially for smaller, start up eCommerce stores, is to set up simple, Flat Rate shipping in WooCommerce.  This video shows you how.