Better Rebels
The rebels got an upgrade, they are much stronger players now, they will no longer randomly declare war on you. But they also are no longer the push-overs they once were. Be careful!
Authority System
Your empire now has an authority stat, this is the amount of authority you can emit to your newly settled and conquered planets. New planets require this authority to not fall into rebellion and you can lose the planet.
This new system will in the future lead to new ways to influence other empires.
Newly planets start out with 50% loyalty, for every week your empire gives the planet authority, the planet's loyalty will grow to 100%. Where it will stay and no longer need imperial oversight to maintain its loyalty.
If you do not provide the authority to the planet, its loyalty will drop slowly. When it hits 0 you will lose control over the planet.