Rokshield shares design elements with cases such as Rokbed, but executes on them in much smarter ways. It comes in three pieces: two slide together plastic components lined with soft fabric and a rubber bumper that snaps in place over them. The back of the case has a number of ridges and valleys, plus an opening over the Apple logo, which we’re typically not fond of. Users can choose whether to install the bumper, but it makes sense to do so:…