I never had a problem with Marg's character, Catherine. I liked the Old Vegas connection she had, although it was a way better story when Sam was alive. Even after he was gone she was often referred to as "Sams little girl" by some of the casino characters. Out of all of them she was the one who was a part of the city & it's past & present rather than just another CSI who could be from any city. I liked that.
My favorite episodes are the ones where they feature Las Vegas history & it's quirks. The type that couldn't take place anywhere but there.
I'm going to miss that connection.