They purposely made them out to be stereotypes. It was supposed to create lots of drama. Also, it was a good way to add character depth by having them defy their set stereotype.

they do have a diverse set of characters,but i would say stereotypes

Well of course they are stereotypes, although I don't think it is a negative thing.To have made so many characters in a show which you have to chose which character you want to win,it would only be right to make each character completely different from each other. If they all were the same then it would be hard to choice person you wanted to win along with it would get boring. It isn't as though they are making fun of people who act like the characters in real life, infact they are showing the better side of most of them. In shows with try out tapes, the people picking the ones who will be on the show try and go for complete opposites.