Well looking at the Ambassadors I think the major problem with the factions is they were too "Flawed", now I can see the merits of Imperium of making it so warfare is effectively controlled under their watch so nations don't throw waves of youth and aimless adults at a political problem aw...

Another problem is the factions, the factions are as some people states, unlikeable with the sole exception of Terra Salvum. I don't know what the new diplomatic faction would be like but it probably be as awful as the other factions out there.