Same mod, different name, The Galactic Empire, the Rebel Alliance, the Black Sun Pirates, and the Droid Empire, fight for control of the galaxy.
Since most of the mod is Fanon, why not? The Lusankya will be designed to be superior to the Empire's Executors, due to the Rebellion's upgrades to the ship. It will also be equipped with lasercannons for use against starfighters. Wookieepedia says this is something the Lusankya was built with since it was designed to focus on planetary occupation without a need for supporting vessels. The Lusankya can be built if the Rebels control Thyferra.
It will be commanded by Wedge, which means there will be two of him. I know that weird, but he was the more well known commander. Adding the Lusankya should balance things out, but if needed, I might add the Guardian.
And yes the Empire has more SSDs, but the chances of seeing another isn't very high, except for the Executor itself. Also the Annihilator no longer spawns in at Tech 5, it has to be built now. Besides those are the Reaper, Terror, and the Iron Fist.