So, Ushgarak, any plans for prequel? It would be more interesting than Rebelion Era, at last for me.
Also( Small Spoiler!)
In ROTS Sidious says: "Once again the Sith shall rule the galaxy!"
It implies that Sith ruled most of known galaxy during last Sith War, but Jedi sucessfully led a rebellion! Propably infighting among Sith allowed Jedi to win?
Yes but there is a huge diffrence- Vader and Sidious were only Sith Lords, and ruled with iron fist for over 20 years.
On the other hand, the Sith Empire without rule of two would require very powerful Dark Lord to do not let it fall apart. There would propably be diffrent Houses/Clans, leader of each both trying to become the supreme Dark Lord and avoiding backstabbing by lesser members of his House.
And after Jedi seem defeated, that would be nothing to hold Sith together for a longer period of time. And Jedi could pull the thing Bane and his sucessors achieved later- stay in shadows, then lead a Rebellion when Sith are fighting each other.
Does it sound plausible?
It can't. The current Dark Side game is about survival. The Dark Side normally doesn't survive because it kills itself. With the whole Galaxy against them as well, the Dark Side players cannot survive like that- they have to try and be different- and the Animosity system exists to show direct consequences of failure there.
That is why a Sith game will be very different- teamwork will become a hazier notion.