myfriend: The most important thing to look for is a tznius’dik girl.
oomis: Tznius does not confer the status of a girl with good middos on anyone. It MIGHT, but there are lots of girls who dress a certain way to be tzniusdig, who are selfish, self-centered, pieces of work.
Sister Bear: You can’t judge a girl based on her mode of dress.
I don’t think that myfriend was only referring to mode of dress. Tsnius is about the way a women acts, her dress is just part of it.
That being said, tsnius can be a good indicator of good middos in general, but as mentioned above some girls will be very tzanua but have issues with other middos, others will have a nisayon when it comes to tznius but be a baalas middos tovos otherwise. You have to look at the whole picture.