>Mai
I feel like only girls who are into betrothed or pre-2010s shoujoslop would be into her. She's essentially the man in the relationship and you just need to be her emotional support princess despite not having amazing characteristics.
>Satsuki
I think she's the most normal of them all. She's also the only one so far where there's the thrill of the chase. The hurdle isn't too high either since she's a broke bitch with no friends, but you would still have to put in a lot of effort. Her best aspect is her low maintenance, but I can see her being unappealing because of her standoffishness
>Ajisai
She feels like the male fantasy of wanting a deredere. It is like she was written as the heroine for one of those trashy one room LNs. She's more appealing than Mai, but unlike Satsuki who would call you a nigger straightup, dealing with Ajisai seems like it would be trying to navigate through a minefield. She's definitely the most high maintenance and emotionally draining.

And that's why as a cis het male I think Kaho or Haruna are the best long-term waifu