Well, OK, let's talk about Sakura.
Personally, she's my favourite character. What I like about her is her mental strength and general kindness and niceness. Despite everything she's been through, she still lives as normal a life as possible given the circumstances, and is a fundamentally kind and caring person. Further, despite all the years of torture, when Zouken wants her to fight in the war she has the strength to say "no", despite the fact that she fully expects to be tortured. Additionally, in HF, she sent Rider up against Zouken when he was attacking Shirou, despite the fact that Zouken could easily have tortured or killed her for that.
She's smart, kind, caring and actually very strong. True, she ends up turning Dark in HF, but she's under a hell of a lot of pressure from AM, and even then she showed a hell of a lot of mental resolve to hang on for so long despite the pressure from AM.