Personally, I'd rate the heroines as follows:
Naruko > Miyu > Tsubaki > Tsubomi > Kirara
Why? Because that's how much I liked them. It's as shrimple as that.

While I didn't like Kirara as much as the other girls, I respect how defiant she was and even in her utter defeat managed to drag Suteru down with her, ultimately proving her love superior to his hatred.