You know what my favorite headcanon for Kara is? That she is asexual. She can be any kind if romantic you want, but I have always thought it made most sense that Kryptonians in general were mostly/all Ace.
Kal-el was the first natural born baby in generations. I don't think that bodes well for the idea that they are sexual in nature. Kryptonians are pretty uptight, and they are probably more interested in science and learning than they are anything else. Kryptonians are a different species from humans, the way their bodies work is going to be different, and they have had time to evolve since they stopped natural births. So its not that far a jump to say that they just wouldn't feel that much sexual attraction as a whole species anymore.













