I think it shows a profound lack of trust in your people if you automatically believe they won't do the right thing.
When I fly, I usually wear a baseball cap under my headset. Am I stupid enough to wear it outside of the airplane? Hell no. As soon as the squat switch in my ass opens up as I get out of my seat, the hat comes off. Shockingly, the hat even stays in my bag if I happen to have a VIP onboard. It's scary how smart I am sometimes.
When I was a young LT, I wore a subdued tab patch with a silhouette of a Herk. Most everyone else in the squadron wore some variation of that. I didn't have to be told not to wear a patch with a stripper on it, or even one with my school's logo. I knew damn well that if I did, I was going to get the stink eye from someone in the squadron, or worse yet from the DO or CC. I didn't need it written down, nor did anyone else. We had enough sense to know where the line was and policed ourselves in those rare instances when that line got crossed. SQ/CC's rarely, if ever, got involved, much less WG/CC's.
Put a little trust in your people, you might be surprised at how they respond.