I've noticed something interesting about the show: each of the storylines has revolved around a specific quadra, more or less.
Hiro Nakamura: INFp
Ando Masahashi: ESTp
Claire Bennet: ESFj
Mr. Bennet: INTj
Zach: ENTp/INTj?
Mohinder Suresh: INFj
Isaac Mendez: INFp
Eden McCain: ISFp
Dr. Suresh: INTp?
Nathan Petrelli: ESFp
Peter Petrelli: INTj
Simone Deveaux: ESTp?
Niki Sanders: ISFj
Micah Sanders: INTp
Matt Parkman: ISTp
Audrey Hanson: ESTj
Charlie: ENFj?
Sylar: INTj