Get to the camera quickly
I remember how Cartier-Bresson carried the camera over a shoulder hidden from view and when he saw a seen he would hold the camera in his hand with the strap wrapped around his wrist so he could quickly capture the moment.
The narrow Gripper strap isn't notices, but it is hard on the camera sometimes to be banging around on the shoulder. Alternatives are to keep it in a Protective Wrap (A bright yellow wrap would be great for that Yashica) and put it in some other bag, like a purse, book bag or briefcase.
I like changing lenses and carrying extra data cards, so I find it easier to have something like the Belt Bag which will also hold a flash and maybe a water bottle.