For me Kali has everything, she is smart, kind and to me very attractive, she has that sexy nerd look I love, her body is great, and I usually pick her to sleep with. I personally would marry her above all the others. I like Kate, be she has more of an android personality. I do like Maria and her story is heartbreaking... so I would always help her. Ashley is kind of a sad story as well, she is a bit unstable. Autumn is too religious for me. The Twins are ok, but they started out very mean.Interesting. She's my favorite by a good bit, but a good way down my scale in terms of looks--I'd probably put Maria at the top; Kate, Moon, Felicity, maybe even Autumn (in no particular order) still above Kali. I guess I prefer a slimmer build (though Ashley overdoes it for my taste), but that doesn't quite account for Autumn.
Where Kali stands out for me is in the relationship--she seems most like "my girlfriend" among the LIs. She's affectionate, but not scarily so like Ashley (though Ashley's mellowed a bit as her story has progressed). Autumn will probably catch up to her in this regard. Maria seems much more FWB than girlfriend. The twins are certainly important to the story (increasingly so with 0.18, and likely more so going forward), but I'm not feeling it in terms of relationship.
Anyway it goes to show you how you can make a harem game and each girl will probably be someone's favorite.
peace