It's an awful thing to hear when playing the game. But the Death Star count down is something that didn't happen in Rebellion. I remember my face when the Death Star appeared and destroyed one of my planets - utter shock!
The fact you know the DS is being built kind of takes away from the surprise and of course then you have to raise your game and defences. Hopefully with the expansion you could bribe a planet and it could reveal info about it but lets bring back some element of surprise to the game!