Unfortunately, many popular DAZ female models are simply ugly, with faces like the unfortunate victims of botched plastic surgeries. The most obvious example is A Wife and Mother. The main character looks like an aging woman who has spent a lot of money, but the result is bad. The face is unnatural. Her lips and nose are horrible.
Such women have too rough a face, there is no grace in it, they look more like trannies than biological women. Feminine trannies exist only in anime, but not in life.
Why do such ugly women turn out? Artists suffer from the same disease as those who have many plastic surgeries but necessarily turn into freaks. They're trying to reach the ideal. Why does everyone have such small noses like children and necessarily thick lips? Even porn actresses (except the obvious freaks) have pretty but normal human faces.
All people are not perfect in appearance, even popular movie actresses and porn actresses. We even know many cases where plastic surgery to improve appearance ruined careers. The character should not only be attractive, but above all recognizable, then we perceive him as a person.
The easiest way is this. You have to take someone's face as the basis, and morph similar ones, giving special attention to the oval of the face, the nose, and the lips. You don't have to make the character look perfectly like the original, although you probably couldn't even if you really wanted to. No one is gonna sue you.
Look up THE MOST BEAUTIFUL PORNO ACTRESSES on the Internet and you will see a huge variety of non-perfect noses, lips and eyes. Maybe some of the girls have had plastic surgery, but it's not obviously noticeable and doesn't lead to ugliness.