Now I see where you were leading with the Julius Caesar reference. However, Ptolemy was a contemporary of Alexander who later became King of Egypt. It's not a stretch to suggest that Ptolemy could give a first hand account as a narrator. I guess it might have been interesting to frame the film with Julius Caesar giving his adopted son Augustus a history lesson.
Now that I am seeing more and more clips from the show, via advertisements and interview shows, I'm less and less interested in seeing it in the theatre. As a period piece, I think it is jarring for the disparate accents to be included, especially when one is so obviously affected merely for the movie (Jolie). That layer of acting is something that should be a group choice, or direction. I think I may wait until this makes the cable/satellite rounds.