If some of your characters tend to look more similar, do you find that they are characters who play similar roles in your stories? Say, love interests, innocent seeming characters or things like that?
For instance I feel like people who play the mother roles and matriarchal type characters have a tendency to fall into a specific vibe with my characters. black/darker haired, ethnic women with brown skin.
Meanwhile female love interests are all over everything, weights, heights, body types, complexions, hair textures etc. and so on