I'm not taking anything away from Don Carlo's reign but he also was in bed with Tommy Lucchese and worked with that family and their administration very closely. If I'm not mistaken, didn't Gambino's son marry Lucchese's daughter?

Comparing the eras of the American Mafia is impossible to do, it's like trying to determine if Tom Brady is better than Joe Montana. It can't be done because the rules were different, technology was obsolete and the government's closest friend RICO wasn't written until the 1970's and not used until the early 1980's (Jack Licavoli, Angelo Lonardo, Maishe Rockman Cleveland are credited with being the first convicted by the statute) and then the infamous Commission Case.

While Gambino was certainly a power to contend with, I still find it appalling that he married his first cousin. Sicilians were known for that practice and it borders incest to say the least. IMHO, I believe Funzi Tieri was more powerful than Carlo any day of the week and twice on Sunday.