I've recently been thinking about the reign of Marcus Aurelius, the last of the so-called "Five Good Emperors" and his decision to switch to hereditary succession. What are some of the possible results of Commodus (who was not at all a good ruler) not gaining the throne, and instead having someone else, chosen via the old adoption system, in power? Could this have led to greater stability in the Empire? Could Aurelius have possibly reformed the Empire and codified the changes?