Pip-Boy does have an automap function, so if this megamap will be implemented, why not to put there a map which all of us are used to see, just to compare where are you now.
People, try to imagine how awesome it could be! Nobody said, that it should be 300km long. It could take the same time as now, to travel from one place to another (it's not hard to calculate the necessary distance between one place from another), but it could be much more interesting than staring at a moving point and looking for a faces among the mountains in the world map during it. It's a "real" travel after all! Or at least much more real, than what we are used to see.
P.S. Maybe some moderator will move all posts related to this "megamap" to a separate thread?