All they have is a crappy small city on a jungle planet, which would blow up if they don't keep a 24/7 watch on their lightning spires. Plus they can't go anywhere since major portions of their own planet are now controlled by rebelling slaves, a rogue Sith lord, an invading mercenary army and a bunch of angry Mandalorians.
I wonder how they can ever get something done, when they can't even control their homeworld ?!
Actually, the Empire more reflects reality than the Republic does. The Empire is a standard State in the sense that "War is the health of the State". For the Empire to survive and flourish, it is imperative that it has an outside, foreign threat. Otherwise, what you see in the Empire is what is in game now - infighting, sabotage, loss of direction, competing interests, and so forth.
The Empire needs the war to galvanize the military, provide the Mandolorians with the Jedi and Spec Ops opponents they demand, and give the Sith more chances to attain greater power, Otherwise the military stagnates, the Mandolorians kill each other, and the Sith scquire more power by taking it from each other. This is exactly how the real world works without the whitewashing we give it to make us feel civilized.