Fulfilment view that shows line items
Most advanced inventory systems will show a list of line items from sales orders to be fulfilled rather than keeping it at the sales order header view. This is especially important once you move to advanced purchasing / sales. You need to see the status of line items. What is ready to ship, what is on backorder, what a drop ship and what is coming from the warehouse.
You can't really do any batch actions without that kind of visibility. This also sets the stage for you to move to the concept of pick waves.