I love the idea of a big fight in a labyrinthine space station. Made such a map myself for XWA multiplayer by connecting lots and lots of Repair Yards.
But... I don't like the idea of it being the Death Star.
maybe a parasitic worm is eating darth vader's brain
There we go. Take your nano-fighters inside the cables and pipes of Darth Vader's computerized life support system and take him down by destroying the vital components!
"One of the bitches actually gave birth while she was attacking, and her puppies joined in on the carnage."
--the awesomeness that is Boatmurdered.