I don't know if you are aware of this feature...
In my current game I am trying to monitor the AI.
I am keeping track of Pariden and Kraxis in a tiny game {Conquest only}, take a look at this image for reference:

The "Relations With Us" section changes over time, monitor that and it "should" give you an indication of when to expect an attack. In my current game I am trying to bait the Queen to attack me, but no luck so far.... If I saw Kraxis and Queen Allied, then I would be expecting an invasion soon afterward as I normally don't bother w/ diplomacy other than trading Tech to weaker Sovereigns.
The Queen's Power rating is 29, I think at this early stage mine is around 24ish...It's still early though. Later, her Power went up quite a bit and relations started becoming tense....She still has not attacked me although, at one point, she could have wiped me out with a Level 7 Champion. I had just expanded to 6 or 7 cities and had only militia in my 4 closest cities. Apparently, the AI could not figure out I was vulnerable, and could be seriously set back or defeated with one champion....I assume it is this "We're still settling", because the two champions {one Kraxis/one Pariden} basically starting guarding one area of the map, not sure why...
{If your wondering, Kraxis I guess had a bad start, because he had only 2 cities and was level 3 while Queen was level 8 or 9...So, AI should not have been at all worried about war on 2 fronts}
This next image illustrates what I am talking about:

As you can see in screenshot, Naegach's army has 1 pioneer, and another, lower level hero {assasin iirc}. Just above the highlighted stack is a LvL. 9 hero {Empire} He is unrecruited as yet. Just South East of Naegach is a Kraxis army. That army consists of a hero {maybe Karavox himself, idr} w/ 4 pioneer units....My units are North West, standing just inside my border {purple color}.
The reason I am taking the time to point this out is that the 2 AI armies have stood there now for 60 turns. Maybe there is someone smarter who can explain why 2 armies would just stand there for 60 turns, with pioneers, and do nothing...
The game, at this point, is really just a curiosity for me than anything else. I don't really want to select some "insane" or "impossible" option, just to have enemies with 1.5 more health {or w/e} just standing around doing the same silly routines.
After reading a lot of posts about features, wishlists, bugs, etc. imho AI is the MAJOR feature needing to be addressed: Like Stardock's CEO pointed out, hard-coding vs. moddability - from what I am seeing, I personally would leave 1.2 out there for posterity & modders like HF&mrqp, but remove modding and hard code AI for a separate version of FE. There are just not enough modders that can do what has to be done to reach a UBER_MOD with FE.
Just my 2 rubles on that subject.
S_S