Friend of mine got sick and tired of her packages being stolen. So she took some meat, let it sit out a day or two so the flies could do their job, wrapped it in a box, and after enough time to ensure maggot harvest, left it on her front porch. It was immediately stolen. She did this 3 times with different size boxes. Hasn't had a problem since.
The thing that irritates me about the delivery person is sometimes they'll drop the box on the porch but they don't ring the bell. We're all home, and the box will sit out there for hours until someone checks.
Another thing you can do is have packages shipped to a business. If we're going to be gone when a package arrives, I'll have it shipped to my friend's office and he'll hold it for me.