I think preferences are overrated considering there is not enough screen time for options other than Bella and Nami. Zara and Nia became far more interesting than they were once they got screen time. Sasha's effect is partially because she's so serious and strict, while also being quite gentle and caring when she forgets to be strict and distant.
People love distant LI's it's the unrequited lust thing, drives people to overcome the distance.
Personally I like her personality the most of the main LI's so far, but once we start seeing development, I'll fall for whoever's on screen telling an emotional story