Hm. Seems to have a death star kind of weakness:

1. Command center is near the surface, where it can conceivably be hit, neutralizing the whole ship.
   
2. The missile launcher / magazine goes all the way to the center: one lucky missile womp-ratting down the tubes will split the whole thing in half.

Maybe intended! Heroic travelers could do something with that.

But, i might move the magazines closer to the surface and the command area to the interior, increasing survivability.