Was looking thru the artbook and noticed a few things:

1) While the Death Star II wreckage is well known of course, I think it's part in early drafts might have served as housing the map to Luke (or at least the old Jedi temple) much like the Wayfinder in ROS.

2) There's this interesting Star Destroyer concept with a Star Destroyer that's red and seems to have a small death Star at it's core. While the Trade Federation ships also had spheres, the hole and trench are clearly meant to be Death Starish. I can't help but think of


3) Despite some claims that it was a fan design appropriated by Disney, the wing configuration of the TIE dagger appears in early concept art. Although the rest of the look of the TIE fighter looks like it was used for Solo's TIE brute.


4)Little bonus here, from the concept art book guy-The Mandalorian also used a TFA unused concept, the TIE landing.