I've played several games against an opponent who seems to have nailed down the strategy that makes the Empire unstoppable.
How would you counter this:
1) He has 2-3 Fleets searching the Rebel Base
2) Uses every mission card possible to convert systems to Imperial Loyalty
3) Uses every mission card that allow for extra probe droid draws
Basically, he is able to check 5-8 systems per turn. Considering that there are 32 systems with 6 that the Imperial player already owns, only 26 systems need to be searched. By turn 4, nearly everything has been searched.
On top of that, he subjugates or turns Rebel systems to neutral or loyal, so Rebel production is brought to a near standstill by turn 3.
None of his assignments are wasted on frivolous things like capturing leaders or pulling from the project deck. Or even bothering with systems getting Sabotaged.