I've been playing games like the Total War series recently, and I've noticed that high unhappiness in the cities can cause the spawning of a rebellious army, that would attack your armies or cities.

I was wondering if something like this could be applied to Fallen Enchantress.

If the Unrest level is higher than a value of X, then the possibility of a rebellious army/unit spawning would increase by a value of Y, a higher unrest value could possibly spawn stronger units for this rebellion.