To add a ball detent under an SAO safety to make it more resistant to coming off on its own? I have tried replacing the safety springs on the couple SAOs I have but they still pop off when holstered. I spoke with a Rep about converting them to DA/SA and it can be done but I am not sure that is the route I want to take. Thoughts?

Probably not...Sounds like a holster issue to me. Exactly what holsters, for what SAO pistols are you having this issue with? What you're describing should NOT be happening with a proper holster for the correct model SAO pistol.