Hi there, everyone.
So I got myself to sign in here so I can comment on some of this.
First I gotta say that I´m no beta-tester, so I just have a pretty basic idea of what the game will actually be like.
But that said, I like the idea of quests for the regent.
I wouldn´t want the outcome to be too dependent on luck though.
I know stuff like that from civ4 and it always makes me uncomfortable - mostly it´s either a awesome win or a devastating loss. But even if you could not lose very much through a backfired quest, you still would have lost an opportunity.
So I would rather give the possibility to compensate failed "dice-rolls" through essence, gold or other things - other than just giving the opportunity to simply use essence for automatic success.
Taking the example of the summonde demon - having tried to bind him to your will through a failed wisdom-check, you could be offered the possibility to e.g. sacrifice population, a unit or a building, meaning that the demon is either appeased with a sacrifice, met with force or lured into a building for him to rampage, giving your sovereign some time to rethink.
Quests could indeed offer some nice possibilities of events that really affect your game.
What popped into my mind when I read about a quest of two feuding landlords was an additional choice - if you could choose to banish one lord from your land, this "quest-fluff" could actually become a new ingame sovereign, heading into the wilderness to found a new people and/or to plot his return.
If the game-engine would set up two different characters for the two lords, complete with stats and not just as an anonymus mentioning in a "fluff-text", then the outcome of the situation could depend on the attributes of the banished lord.
Another example would be a quest where you had the possibility to outlaw someone, who then would perhaps flee into the woods, starting a career as either a Robin Hood or a cruel bandit, harassing you with occasional unit-spawns and/or loss of income/ressources on nearby fields.
Apart from this I second the notion that a sovereign should gain experience through other things than just battles or occasional quest-events; Psychoak has offered some nice ideas.
I mean, maybe I think to much "master of magic" here, but for me the warlord-style sovereign on the road is just one of a few types of sovereigns, in reality as well as in fantasy fiction, and not the one I would have thought of first, when I learned about the sovereign concept in Elemental.
There should be sovereigns who mostly sit in their ivorytower, studying magic, ones who travel about their country to ensure their people of their presence, ones who practice and further art and culture, ones who practice and further artisanry, ones who teach and let others teach science, etc..
All based either on the respective sovereigns attributes or on the players explicit decisions.
And either one should gain experience doing so.
Making a sovereign profit from every building built, for example, should even be quite simple to implement.