Personally I see no reason to try and balance any of the game's NPCs or GMPCs. It is, after all, quite obvious that if any of us try to kill Vlad, the great hand of Deus Ex Machina will slap us to next tuesday, regardless of our power. Most of the game's balancing rules don't apply to them since they drive the story and plot instead of responding to it.

That is not to say the PCs do not drive the story. They just do it differently.