It would be great to see some kind of atlas overlay that would show Jesus and his disciples' movements through the gospels.
In addition, it would be intriguing to plot Paul's route (along with his fellow workers) throughout individual epistles as well as across all of his epistles (although, this would no doubt require some editorial decisions due to questions of authorship or dating etc.). Perhaps it would be possible to show how different theories would produce different routes.
Ideally, all incidents would be plotted on one map and would just be numbered/lettered so that each time a place is mentioned, a route or series of places would be plotted out to track progress.