Always one in the chamber for me. Fine motor control goes out the window in a stressful situation. Can you be assured that you will have the control to grip the slide and chamber a round? Also, when every second could count, do you want to lose time chambering a round? I choose not to take those chances.
I carry a Kel Tec P3AT in my pocket, which is essentially the same gun as your Ruger, in a Desantis Nemesis holster. The gun is DAO and has a decent length trigger. IMO, as long as you have the trigger covered, there's no way the gun is going to fire. Guns are mechanical devices, they don't just go off spontaneously. Unless you're playing with the gun while it's in your pocket, I think you're safe to carry it with a round chambered.
Oh, this topic has been discussed, many, many, many times. If you search it, you'll probably come up with more answers to your question than just the responses you'll get to your post here.