this is a great idea, but a few problems I have with posted suggestions, 1: yes, they definatly should use the titan and mod it, however, a titan is small, a capital ship is HUGE, the dev team could use the titan maps from 2142 as a start, but I honestly expect to see a MUCH larger area then that, the dry docking ship idea also sounds good, maybe have some of those big ships in dock, maybe have an objective where the rebels have to blow up several big ships in dry dock inside several hangers spread across the capital ship? and the big ships would have small, less then titan sized areas inside them?  Also, there should be (in my opinion) assault carriers that would take off from rebel ships and would carry not pilots, but troopers with special weaponry load-outs for attacking the capital ship. These troop transports would be kind of like in battlefront, and would move slowly, maybe having a few mounted turrets used by troopers inside, I am sure a 2142 transport could easily be modded slightly (mostly a different skin and sound effects) for this purpose.

The Imperials objective could be to hold out until a set time period at which point reinforcements arrive to back up the capital ship, thereby defeating the rebels?

Another Spacemap:
A Stardestroyer moves from A to B (hyper buoy). The Rebels must prevent that.
1.) Destroy the engines of the destroyer
2.) Disable the destroyer with Ion weapons (I think blow up the engines take less time than disable the monster)  (Does that prevent massive lag?)
3.) Boarding. Capture all the outposts in the destroyer.

1,2 Space only
--> Perhaps the destroyer has important secret plans...

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