Freedmen could become part of the equestrian class, which is basically why they became important
Augustus established the equestrian class because they were efficient administrators, and they had business experience from their time as slaves. (Although not all equites were freedmen...)
There was a 400 000 sesterces requirement to become an equite.
Members of the equestrian class could become the praetorian prefect, a position which was extremely important. Dio calls the praetorian guard Augustus' "personal bodyguard."
Freedmen become particularly influential during the reign of Claudius, when the freedmen Pallas "virtually controlled the empire..." -Tacitus.
Narcissus and Callistus were other important freedmen that Claudius trusted.
Nero hated the freedmen, and during his reign a lot were deposed from their positions- including Pallas.
Tacitus refers to freedmen as "ex-slaves", revealing the contempt that free-born citizens felt towards them.
Freedmen could become the procurator of the grain- which was THE most important assett economically in the entire empire.
Hope that helps.
