Honestly, a lot of your take seems more like personal preference than an actual explanation of the poll results. Saying Ayumi is “boring” or lacks attractiveness is subjective; it might just mean she doesn’t appeal to you. Other people clearly see something in her if she ranked second for marriage.
Same goes for calling Sumire and Sushi Karma “more unique” or saying they have “assets.” Those are value judgments based on what you personally find interesting or appealing. It’s fine to have favorites, but that doesn’t necessarily explain why the broader audience voted the way they did.
It just feels like you're projecting your own tastes onto the whole fanbase.
The poll is based on value judgments in the first place so of course any explanation of why are going to be value judgments in of themselves too.
And you're assuming that i'm stating my personal preferences in the first place instead of what I think lines up with a lot of people's personal preferences. For example, I'd probably rank Sumire 1st for hookup and Aymui 2nd but it would be hard tie between Sumire and Souko for 1st for both dating and marriage and I'd put Ayumi dead last in marriage. But even if my personal ranking is different, I can still think about why other people make different choices and conjectures about why.
It doesn't take a genius to know that people generally pay more attention to eccentric people with big personalities over someone who reacts to things normally. And while other things are value judgments, Souko and Sumire having more assets isn’t. They objectively are more voluptuous physically. They have a body type considerably more popular with most straight men not just in Japan but across the world.
The stuff about why Sumire is number 1 for marriage and Souko last but Souko beats out Sumire for hook up is more of conjecture. But in the end, understanding exactly why people choose what they did is going to be conjecture no matter what, unless you personally go and interview each person on why they picked who for what. And even then, the answers might not be completely honest or aware.