Most of the straps that come with cameras are basic to say the least. I have bought straps for all my cameras.
My DSLR’s are big and heavy, I generally only use them for professional jobs and wildlife. For all three of my DSLR’s I use Optech straps. These straps are easily detachable for when I use the cameras on a tripod, and with there broad nature make the camera easy to carry and feel lighter on your shoulder.
For my Medium Format and Large Format cameras then its a case of no strap required, tripod use only, but for my Leica’s I tend to look out for nice, stylish artisan straps.
My current favourite is the Barton leather strap which while stylish and good looking is a very good strap for a light camera.
I am also looking out for a good quality leather wrist strap.