One of the ways I want to work is to be able to create characters
and save them off so I could later include them in scenes.
To create a character, you would load in the base model. Below is
the base Victoria3 model. Doesn't look very realistic, does it?

To change the look of Victoria3, you would apply a "morph pose" to
her. There are many built-in morphs and you can buy additional morph
packs for Victoria3. Below are some eye morph injections for
Victoria3. If I select the head of Victoria3 and double click one of
the eye morphs, it places a new parameter on the Parameter Tab for
Victoria3's head.