A couple of suggestions:
1. Use the Forsters: they're about as omnipotent as you can get in this aar.
2. Use an unknown senator: a view from someone who can only see things through reports, rumors, and Senate speeches; it would make it interesting for people to try and figure out how things happened.
3. Use everyone: has anyone here read a Harry Turtledove alternate history book? If so, you'll know what I'm talking about. He takes a fairly large group of main characters and jumps between them. For instance, you could take the view of all of the main Senators (McCollum, Gandalf, Forster, Storey, myself, Brad, Misha, Xanadu, Demetrios, C Rex, etc. etc.), as well as the Turkish ambassador (and the scottish ambassador

), the Pope (or Gen. Sarducci/Bishop Gotti), maybe some foreign monarchs/dignitaries, some of the Italian rebels, you get the idea.
I would like to ask that you not just use one of our families (outside of Forster's, due to his "omnipotence"), because it would put too much emphasis on their individual story. This could be avoided if using Forster by simply having the book be made partially of reports to the Don, that type of thing. However, I think the 3rd option would be best. It is, after all, how the aar is structured anyway.