The idea is, basically, You already have rover "hold Bearing" and hold speed, well, why not have a "Enter Co-ordinates" section, so it sets it a co-ordinate to drive towards rather then just a bearing, as you already know how to make things aim for such co-ordinates with the landing auto-pilot and all, and you could even make a "driving path" autopilot easily enough by using multiple co-ordinates that it would drive to the first one, then to the second one, and so on, so it wouldn't just go careening off cliffs to its doom