The rear breaks way too easily, so who cares what color they are? At a minimum they need all titanium except for a small disc on the rear where MagSafe is (perhaps some kind of strong ceramic? idk), as well as the normal antenna bands. Have a small raised bezel around the display, and the portion that surrounds the cameras should also be titanium with a small lip around the lenses. This would probably also make the phone lighter, as I think the glass they use is thicker and heavier than thinner titanium would be. This would also allow for more battery.