Michael Ritchie’s tenure as artistic director of the L.A.-based Center Theater Group will be a delicate balancing act between honoring the company’s past proven successes and seeking new audiences and new directions that might galvanize the theater community in the city. He is determined to make the three theaters under his control succeed without relying on touring Broadway productions, and says that he won’t hesitate to use the star power available to him from neighboring Hollywood to bring in the crowds.