Yeah, like I said in the podcat, I'm going under the assumption that the "unlimited resources" offered up in the question means we can ignore all considerations of technical feasibility and commercial appeal. One of the biggest design problems in games like Savage is developing a good push/pull between player freedom and the chain of command. Ironclad's new DOTA-style game, Sins of a Dark Age, is wrestling with those issues as well.
The thing is, there has to be incentives for responsible behavior at every level of the experience. The kings, governors, generals, and soldiers have to be encouraged through gameplay rewards to behave responsibly within their own sphere, subverting at least part of their will to the needs of other players in other contexts. The potential for player frustration over the game's lack of fairness is also remarkably high. Imagine if Justin as governor of a city does absolutely everything right, but his city is completely destroyed by the enemy because I didn't move forces in to defend him, or because the forces I moved in were misapplied by the local general.