i am using Drupal Commerce since it was beta and know all about the system and how to do what i or my customer want, so a big "Thank you!"
But there is something I do not quite understand:
When the checkout is complete, the order status is pending. However, the order is still changeable. The prices of the line items can be changed if you change the product. That should not really be right? I always complete the order so as coupons in the order can not be deleted.