Yuffie was a good character from a gameplay standpoint because she has the ability to attack from a long range and she possesses a multiple hit Limit Break, "Doom of the Living", which puts her one up ahead of some other characters.

I felt like they made too much comic relief of her story since it is rather tragic that she feels the need to resort to stealing Materia to help her country regain its former glory that she remembers as a child. I heard she has a more serious role as a supporting character in Dirge of Cerberus: Final Fantasy VII.