Why was there lot of economic problems and government corruption with the Roman Empire?

over reliance on slave labor, over extension of boundaries, rise of the eastern empire, corruption/political instability etc. People write books on stuff like this.

Yes, there was a lot of economic trouble in the Empire, but you could also say that it had gotten too large their way of running things.  A lot of the economy worked by constant expansion and they had reached their limits and then some.  I always think of it to how an amoeba is at the limits of the size a single cell organism can exist.  Larger lifeforms are multi-cellular.