Off Broadway vets Keira Keeley and Sofia Jean Gomez will round out the new cast of the Off Broadway revival of “Angels in America.”As of Feb. 1, Keeley (“The Glass Menagerie,” “The Thugs”) will play hallucinating Mormon Harper, the role currently played by Zoe Kazan, with Gomez (“Creature”) as the angel. New cast members to be added for the show’s extended run also include Michael Urie (“Ugly Betty”), who takes over for Christian Borle. Signature Theater Company’s revival of Tony Kushner’s Pulitzer and Tony-winning two-parter, which began perfs Sept. 14, has proven enough of a popular hit to warrant three multiple-week extensions. Current “Angels” ensemble also includes Zachary Quinto, who’ll be replaced by Adam Driver next month. “Angels” is now set to play through March 27.