Mothership does an excellent job of this, as I've written about before. The classes are clearly designed to come with interesting relationships baked-in. We can all imagine how the Scientist and Marine might interact in that sort of sci-fi-horror universe. Likewise the Teamster and the Android.
I wanted to tap into this and expand it for the characters in Voidheist.
The plan was to take Mothership's four highly evocative, archetypal characters, and blow them up to a two-axis grid based on Origin and Occupation.
The Android is clearly an Origin. They exist outside of the assumed humanity of the other three classes, so it got me thinking about what other Origins would exist. These would be applied onto the occupations, so in Mothership terms you might have four androids that all have different functions, or four scientists that all come from different backgrounds.
I wanted these Origins to key into the major elements of the implied setting and give the GM inspiration for creating scenarios, but also wanted them archetypal enough that you almost don't need any explanation beyond their name.