Due to the Casino skims and unions, among the other everyday money making schemes, I think Chicago was making money hand over fist.

Remember they had Murray Humphreys out there bribing all the politicians, that had to be expensive. They were making as much money if not more than the NY Families at their peak in my opinion, mainly due to the Vegas skimming.

As much as I would like to say Pittsburgh, I would say Chicago made the most money outside NY, by far.

But I do think Pittsburgh had much more money, influence and power than many other outside of NY families, just not the most. From the casino they owned in Cuba, to California, to Detroit, to NY.
During the 1960 World Series, John LaRocca hosted a group of Outfit big shots in Pittsburgh and got them tickets, the FBI has photos of them together at the game(s).

*Honorable Mention*
I think Trafficante may have had more money and power than given credit for because he had legit relationships with every single family in the country. I think he was getting a piece from many families who operated in Florida.