When PCs are Leaders and they deal with Kings, Armies, Bureaucracies and States

TL:DR - you still have to do important stuff yourself - you cannot delegate the most important jobs. This becomes more narrative and requires a basic concept.

Work inspires me to game, or more accurately, it frustrates me in so many levels that I really love to escape to the game. Still it is my source of inspiration, insight, and ideas. One idea that seems not to be accessible is that - higher up the food chain you still have to do things yourself. Of course you can pick and choose your challenges better, you can allocate that epic agent for infiltration, you can send your armies, you can mobilize your entire economies... but in the end of the day the only person who you have the ability to predict what is going to happen is yourself. 

Your army can fail, worse - get turned, captured, or destroyed. You spy can fail or be turned, or was actually a double agent. Your generals can turn on you, while you delegate on an important task (happens a lot in history), your Bureaucracies can be a mess, your economy is really not under your control, and there is nature, and your Enemies. If your GM enforces fair manpower limitations - that Awesome people don't show up ready to be employed under your command (and mostly people who "say they are awesome" but are actually crap or worse - traitors), then you cannot just get rid of them (as Alexios Komnenos case was a great example - so many traitorous generals and he cannot afford to kill them, frequent assassinations and betrayals). 

The only people you can count on is your "TEAM". Although your team is not like what they used to be, fighting side by side. Instead each PC has a small staff which is Role-Played by the other Players while their PC is off doing something. All Players are in the scene, but in different characters. One character has to negotiate this, spy on that, lead this army to this, ready a city for that, etc... 

In the end, the GM goes through Each Scene, and through each player playing their part. Of course in some scenes some Players are controlling the more Powerful PC, but everyone gets their turn in the spotlight. The same way we wait our turn to act, we wait our turn at the spot light. We wait our turn, but the GM can make our wait interesting by letting us affect the scene through Allies that we can take control. 

Format or How this Works

1. Basically the GM reviews mentally the entire process. Diplomatic, Logistics, Administrative etc... Its that intimidating because the GM's mind just swooshes past the entire process and sums it up. There are many variables in every process and he just arbitrarily (or based on the character's weaknesses) introduces challenges that typically comes up.
1. Ex. A weak diplomatic corps but competent Military. This can present problems such as the risk of your diplomat being turned or losing focus on the leaders best interests. Lack of personal initiative or resourcefulness. Etc... Even if the Diplomatic Corps is lead by a PC, and the other Player play the NPCs staff there are tuns of problems that can going on. 
2.  Ex. An Army on the March, Marching Discipline, Weather, and Problems with the Locals can be the mini-adventure or challenge within this side of the game. Again the leading PC, and minor PCs representing the other Players 
2.  The GM moves back and forth. Even if the players are aware of things they should not be, the GM can always adapt things and expectations. If the other players learned of a spy in the army or diplomatic corps, or in court the GM can just say - you learned the spy's name. I wont say to maintain assymetry but I will guide the actions of the character who knows it OR he can just present a hard penalty to detect motives. Always giving the impression of a red herring can help players choose the best economize their characters time. 

Economies of PCs Time. Simply adapt the Multi-tasking penalties or Rapid Strike penalties to a situation. One task and every additional task is -2 (from Spaceships Multi-Tasking).

In hindsight, I think I should have made a flow chart for this (although it is more time consuming). Anyway, if there is a demand for a particular modular process I'll make it. I guess its some Economic Rules of thumb people can fudge of make assumptions to model how large and complex organizations interact (some Psycho history lolz)

The Campaign, Sins of The Crusades is a publicly view-able game and learning experience in running such games.