Michael Franzese took over his father's crew when he went away, or at least started initially getting involved because his father was away. No way he wouldve survived that long if Sonny wasn't so powerful under Persico.

Ironically, one could make an argument that Carlo Gambino and Joe Bonanno were powerful because of their families. They were both from mafia royalty in Sicily, so they immediately had respect when they came to the states.

John Gotti is someone who had no family connections and rose in power simply due to brute force and his charisma. Horrible boss, but he still got powerful on his own. Carmine Persico was the same way, from a middle class family with no mob ties if I remember correctly.

Like George A said: "Never make a poor man the boss." Maybe that's why Gambino and Bonanno were so respected for so long, because they already came from mafia backgrounds, had decent money, and weren't petty street thugs. Then again, it didnt help Castellano in the longrun.