My final thoughts... It's not just a question of numbers. Yes, the GE have a larger Empire, more troops, more and better ships. But it's also the infrastructure. The GE's infrastructure is an order of magnitude greater than what they SE has. The SE has had control over most of these system for only a couple of decades at most. Much of the infrastructure was damaged during the war with the Republic. The GE has a much more stable situation. Industrial might, much larger armies, many more ships and the capability to crank them out faster than the SE. This is about power bases after all. The GE is an unquestionably stronger power base. The only way you can declare Vitiate winner of a Kaggath against Sidious is if you allow for some sort of gimmick. Vitiate's brainwashing wasn't strong enough that he could use it to defeat the Republic. Why should we believe he can use it to defeat the GE? And that is really the only way you can declare him winner. You can just as easily imagine a scenario where Sidious corrupts one of Vitiate's strongest Sith and takes him/her as his apprentice to spring a trap on him.
Good point. However it can be countered.
To say that the SE "infrastructure" isn't as good as the GE's because they just went through a war seems a little odd. I agree that the GE's infrastructure will be a bit better, but not by a lot. The GE did just experience the Clone Wars, which was the biggest war in Galactic History I believe. So to say that the SE's infrastructure would be weak due to war is a little contradictory.