I'm working on possibly creating the first piece of this battle for a map. Basically just a massive Cap Ship Battle, but obviously not containing all 34 ISD and the SSD. It will most likely be some number of ISD vs Home One, some Frigates, and Possibly a couple more Mon Cal cruisers. The turrets on the ISDs should be mannable and destroyable and the goal will basically be:
Empire - Destroy certain % of Rebel Fleet
Rebels - Survive for a set time limit without getting pushed back (vary per map size probably)
There are some tweaks coming for space battles that should make this massive cap ship on cap ship assault (Obviously there will be fighters available as well) quite enjoyable.