Surprised no one has commented on this. My take would be first of all it depends on the camera. None of my 6x6 nor even my Zeiss 6x9 have straps, other than a hand strap on the end. My Rolleiflex has the normal one that comes with its Yashica case. My Super Press 23 has a wide strap that used to be sold for 35mm cameras. It is strong enough, and sure helps spead the weight on my shoulder.
I think whatever will fit and give you what you want in carrying ability will be fine. That simple.