It would be very helpful to create a feature where you could add a weight to the "Custom Packages" section (Settings -> Shipping -> Packages -> Custom Packages Tab). See screenshot below.
That way if you have all of your product weights set up, the product weight and box weight could auto-calculate to have a final shipping weight (see screenshot below). Right now it is very manual. I have product weights set up but it does no good because I still have to add the weight of my box to the weight of my product(s). This would optimize workflow tremendously!