Well, I always thought LYF's skin looks more radiant and translucent than LSS', which gives LYF an out-of-this-world look. LSS is always described as more earthly looking. Was she that bada$$ as Yan San Niang? I wouldn't say "bada$$" as San Niang fights for justice, believes in the common good of people and doesn't go around murdering innocents and being treacherous. I don't think the character's even "grey" in any way. I'd say San Niang is feisty. Serious bada$$ sh*t is Nicky's 4th Prince
(OK, I admit to a masochistic streak in being attracted to murderers).
LSS? - don't think she can ever pull it off as a murderer or doing underhanded things. She looks too innocent and righteous to be able to come off as devious in any way, just like Hu Ge and Wallace Huo.
I'm still iffy about Hu Ge's recent attempts at looking bada$$ (5 o'clock shadow and dyed hair?!) and taking on a villainous role in Tian Zhi Hen. If he wants to break out of his good, kind & honest soul roles, he should do what Wallace Huo did in Detective Tang Lang. Wallace knows he can't play devious villain roles, but he can play someone who's cool & tough-talking but still upholds justice and doesn't resort to underhanded means.