I don't know if anyone will have chrome roof racks. I asked about this awhile back on whether the '03 and up Navigator chrome roof racks would bolt on.
Oddly enough, the chrome roof racks on the new Navigators look the same in design as the previous generation Navigator. Looks almost like no change. It might be conceivable that the chrome racks from an older generation Navigator might bolt on, but who knows.
As for door edge guards, you can get chrome plastic molds that just press onto the door edge and is held on by an adhesive.
Metal will have a nicer contour though because it's molded to fit the door, but they dent and scratch when actually hitting something. The plastic ones won't.
Just don't get carried away and start chrome stripping every single edge on the truck (doors, hood, lift gate, etc...)
8O)