I am a range safety officer at my club, and I end up talking to inexperienced shooters about a wide range of issue, including different styles of handguns, and how to carry them.
I feel that most shooters are best served by striker fired auto pistols, with triggers that are not too light, and with no external safeties. My reasons for this preference include most of the reasons given earlier in this thread. And I also frequently discuss with people how quality holsters are a critical piece of safety equipment, and how concealed carry handguns should be carried with a round in the chamber.
However, there is a larger and more important principle that overrides all of these preferences. Everyone who carries a firearm should carry it in a way that they are comfortable with, provided that their method is not less safe. So if someone only feels comfortable with a manual safety, or with a DA/SA auto that can be carried hammer down, or with an empty chamber, then all of those choices are OK for that person. That comfort level is likely to change over time as the person gains experience, but it might not, and that is OK too. No one should try to carry a firearm in a way they are uncomfortable with.
We often say that if your gut is warning you not to do something, then maybe you shouldn't. In some situations, we call that feeling "situational awareness" and commend people who follow it.
When someone tells me they want to take extra safety precautions that experts say are not necessary, I consider whether their gut is telling them, and me, about their actual training level. I take that as a hint to talk about training instead of gear.