Why Were Solidad and Ursula Added So Late?

Woah, I think that's a little harsh. I got sick of the character very quickly, because I found her personallity, interaction and plot-related issues to be extremely tedious. I have nothing against a rival being taken in a different direction to the norm (hell, I want another friendly one just so it can handled differently), but that's not all that constitutes to being a good character :/