I disagree with step one. Leaves you way too vulnerable to theft, extortion, and just plan rating. Hell they might give you up if they get busted for something unrelated to make a deal out of their mess.
You're absolutely right. Your shipping contact might get busted for an unrelated petty crime, and to make the charge go away, he can say, "Hey, I'm getting shit tons of drugs for this other guy. In fact, there's a package coming in next week. He sells to tons of people..."
The point is, never outsource your security and keep as few people involved as possible.
4. Have a runner pick up the packages for you after 24 hours
Have you never seen those cop shows? They'll flip 3 or 4 people in a row until they get to the main guy. A human in between you and LE offers zero security. Don't get more people involved. That's just more people who know about your business and who can rat on you for unrelated reasons.