Is there a way to just have a battle between two armies? If I got the games I wouldn't really be interested in doing any of the turn based strategy, or at least not starting out.
Finally, and I may be wrong on this, I remember reading that the later games have an option to disable a lot of the turn-based micromanaging stuff. Not sure if this is actually a thing now as I haven't played them myself, but this would allow you to play through the campaign with most of the managing and politics being let to the AI to handle while you just focus on the actual warfare and troop creation / movements.