From what I've heard people in the south have painted themselves into a corner. To start a war many of the rulers would basically need to do something that goes against their established characters. There also doesn't seem to be a big enough dissident group in any of the realms to stage a take over and shake things up. What we need is for someone to just go insane and get things started.
Does a reincarnated original FEI realm founder slash self-declared deity returning to the realm who betrayed her and her people count as a shake up?