the characters I find the most interesting and would like to read more on or hell lets say for fun/hypothetically I could actually sit down and talk with them:
dead:
the chin gigante*
roy de meo
lucky
meyer lanksy
carlo gambino
gotti sr*
dellacroce

*yes I know there is plenty of info, but its different to sit down face to face with a person willing to just shoot the breeze

alive:
gaspipe
sammy the bull

again, I know there is plenty of info out there on these two, ready above.