Ironically, Rei has higher standards than Asuka when you think about it. The former ends up with the alien twink prettyboy chad with literal angelic looks (Kaworu) and the latter lands an unremarkable ricecel that needs glasses (Kensuke).
This runs contrary to initial expectations where upon first inspection, one might arrive with the preconceived notion that Asuka, being the insecure spoiled bratty princess that feels entitled to everything, would try to snag the biggest Chad she could find. And Rei being more befitting of the quiet soft spoken nurturing Yamato Nadeshiko archetype so idealized by Japanese men and by extension otaku, would be more modest and humble with what she searches for in a partner. I applaud Anno for so thoroughly subverting our expectations like this and deconstructing Japanese cultural norms and ideas of femininity as represented by Rei relative to Western ideas of what defines feminine qualities as shown by Asuka. These two being compared and contrasted demonstrating the difference in cultural perceptions of what traits and tropes each side find the most appealing and desirable in their ideal for female characters during the creative process of designing and writing the personalities and tropes they follow.
Either way, both of them found a better choice than Shinji, who's a mentally ill nervous wreck with high inhibition and a confirmed dicklet with daddy issues.
TL;DR: don't watch Evangelion and just jack off to the girls, it's a better and more productive use of your time