All my opinions follow, just add 'I think' or something equivalent to each line.
Not fantastic but better and improving.
His face is darkly shadowed and with a bright hat and bright shirt, his face is not the center of interest.
trim away the stuff you con't need and improve the composition.
lighten and sharpen the face and dull everything else, then convert
You aren't composing and exposing for the important areas - the face.
Here the face and hands are at unimportant areas and the face is deeply shadowed.
It is an absolute fact that dark skin needs more exposure than light skin.
Shooting dark-skinned people in contrasty light is a real challenge and none of the dark-skinned subjects are exposed well.
Nice composition, although off to one side for no artistic reason.
Highlight on head is blown but ignorable.
Face is well underexposed but sort-of fixable.
Fill flash or reflector would have made all the difference here.
Or better, shoot in softer light.