Very few emperors died in their sleep. On the one hand you could have a few years where you could do almost what you want. Set against that you would probably find yourself a powerless fugitive and dead after a few years. Also set against that the life of an emperor was often that of a life of trudging thorough mud and drizzle on the frontier and then having to buy off the enemy with almost unavailable gold. If all that task was delegated the general on the frontier might decide to try his hand at your job.