Complex sentence: Luciano abolished Maranzano's title of "capo di tutti i capi", believing that the position created trouble between the families and made himself a target for another ambitious challenger.
Split into simpler sentences: Luciano abolished Maranzano's title of "capo di tutti i capi" or "boss of all bosses". Luciano felt that the position created trouble between the families and made himself a target for another ambitious challenger.