Is the Trapani faction still the most powerful faction within the Sicilian mafia? I kinda get the idea that several Palermo clans are still plenty strong due to their American operations.
Also some of the Agrigento clans are quite international in scope with links in North as well as South America.

Ndrangheta got tons of clans that are widespread. There's a well known clan that allegedly operates in my area. They're basically ghosts though, extremely low-key.