As a developer who writes an order export for Magento2 you would expect that besides the getBillingAddress there would be also a getShippingAddress method. While all the [g/s]etShipping... methods exists in the Magento\Sales\Model\Order model (which is the actual implementation of the OrderInterface) those elementary shipping-address methods are not part of the API interface.
Example: $order is declared as type Magento\Sales\Api\Data\OrderInterface. Practically the code "$order->getShippingAddress()" works but from a declarative view the method does not exist in the API and the implementation therefore is technically wrong.
While it is understood that not all orders have a shipping address (virtual orders/goods) the majority of orders processed in ecommerce actually have a shipping address. So the shipping-address methods should become part of the OrderInterface like it is already the case for the billing-address methods.