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.Kali is one of the most beautiful girls.
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.