I have always considered the ringflash a light that can fill many roles. When used on camera it does produce a rather flat light that many fashion photographers use to their advantage to produce high key “fashion” type looks. When used with the subject in close proximity to a backdrop, it can produce some very unique shadows.
Off camera, it can be used as a key light or a fill light. It can also be used in a clamshell type of setup for headshots. In bright conditions outdoors, on a stick, on a light stand, in the studio, mounted on a tripod as a fill light, it has many uses.
I have placed a large soft reflector on my ringflash with a white diffusion cloth clamped to the dish using simple paper clamps.
One light – many uses.