Most exciting division: 154

[SorceryatCaesar]

Not because of the champions.
Because of abundance of good challengers:

Sergio Martinez, Alex Bunema, Alfredo Angulo, Joel "Love Child" Julio, James Kirkland, John Duddy, Ronald Hearns, Vanes Martirosyan, Joe Greene, Deandre Latimore, Julie Cesar Chavez Jr.