Rebellion was a disappointment when it was released. It was supposed to be an asymmetric conflict, but the games plays the same for both sides. There are some differences, but only in details. Coruscant and the Deathstar vs the mobile HQ of the rebels. A couple of units have different abilities. The strategic part is the same for both. The allegiance of planets was always visible to both sides, planets could be conquered or acquired by diplomacy, the outer rim had to be explored.