This setting affects the apparent radius of spheres in the sphere representation. Default scale is set to 1.0.
# set the sphere scale to size for selection.
cmd.set ("sphere_scale", size=1, selection='', state=0, updates=1, log=0, quiet=1)
# generally it's simpler to use the console form
set sphere_scale, size, selection
# you can print the current value for sphere_scale
get sphere_scale
Using 0.25 gives a nice balls&sticks representation with both lines and spheres turned on.
set_bond stick_color, white, (all), (all)
set_bond stick_radius, 0.14, (all), (all)
set sphere_scale, 0.25, (all)
show sticks
show spheres