I don’t think it’s a matter of aesthetics. The Vostok was spherical because they couldn’t figure a better shape, the NASA did more research on spacecraft aerodynamics and particularly heat shields and and come up with the conical shape with an ablative heat shield on the bottom. The Soyuz eventually settled for a dome-like shape for the reentry module.
I don’t think it’s a matter of aesthetics. The Vostok was spherical because they couldn’t figure a better shape, the NASA did more research on spacecraft aerodynamics and particularly heat shields and and come up with the conical shape with an ablative heat shield on the bottom. The Soyuz eventually settled for a dome-like shape for the reentry module.