My main issue is that skin tone genetics (and all of the genetics, really) appear to be bugged. I believe it has to do with the undertone.
For example, if a Sims with warm, light-colored skin has a baby with a Sims that has neutral, light-colored skin, it will often end up with extremely dark skin out of nowhere. It can be fun if this happens extremely rarely, but, at least in my game, it's nearly every single time. Genetics used to be one of my favorite parts of the game, and it feels broken now.
As for the randomly generated townies and their names, I feel similarly. It can be fun for storytelling to have a Sim that doesn't appear ethnically Japanese to have a Japanese last name, for example, but it feels extremely disproportionate when I have several pale blonde Sims and deep-skinned Sims that have Japanese last names. I love diversity in the Sims and having a good mix of different cultures and appearances, but I want it to make sense. This just feels like a bug.