So many poor “design choices” in human anatomy. (Note, I know there’s no intelligent design).
The optic nerve. External testicles. Lack of decent fur. The way some nerves and blood vessels are routed make zero sense. An immune system that often wants to kill you. The list goes on. I’m sure a biologist or medical person could add plenty more. Many animals have some of these traits, too. If some trait or process is just barely good enough, nature will chug along with it for millions of years. Nature is all about some redneck engineering.
Good catch, I forgot that one! And the other classic is having waste excreting plumbing and reproductive plumbing all bunched together.