With better luck or better leadership, Rome might have survived.
The Roman Empire did pretty well -- the stretch of time from Rome's conquest of Ostia to the fall of Constantinople is over 1800 years -- and it was accomplished without a postal system, public schools or general literacy, a banking system (other than the loansharking style), common liberty (lots of slavery, and lower classes were always at risk of sinking into it), and a coherent system of succession for the emperor were some of their problems.