I agree, they do look different, but they're both hot, so I don't see the point in changing them. If anything I could understand possibly changing Liza's lips to be a little thinner, and maybe make her nose a little thinner and longer. I have noticed that she looks mixed race... but whatever. It's not a big deal.
Depending on how dramatic the changes are, it might be jarring to go pre-change to post-change in the middle of the game. I certainly wouldn't expect Perv to go back and change all the previous renders with Liza's updated face.
In the end, the vast majority of us are happy with them as they look, so I don't see the point in changing them.
"These twin sisters make us rethink everything we know about race"
Uh what? I'm guessing they're fraternal twins of mixed race parents. Exactly what should I be rethinking here? lmao