This ^ was typical in "Master of Magic" and made the games a lot more fun and challenging. It's all too easy for the player in many games to form alliances with the AI and then Crush them piecemeal throughout the game (Age of Wonders anybody?).

So, I prefer an AI like this and although I will still go for an alliance or peace with them I'm always leary of a backstab or attack much like in the Total War series which I really enjoy.

I almost wish they would just take diplomacy out of these types of games because they aren't ever really real alliances and we all know how we are and that "WE" will be the first to break them given the chance at a later time in the game. Never understood why anyone wants to play a wargame strategy game and expect to win "peacefully". lolol  All players are really doing that want alliances are buying time for themselves to build up and become more powerful.

In my first playthrough I went on easy/easy, large map, 8 A.I's, epic research speed.  I was taking it easy killing monsters and having fun, learning the ropes as I skipped the tutorial. I had 2 cities and was planning on my third and fourth.  

Then Magnar shows up, grabs one of my city spots but I think, ok we can Coexist peacefully. I go my thing going killing monsters and stuff.  He declares war on me.  I trounce him grab 2 of his cities and am feeling pretty smug....until I meet the other 7 A.I's who all declare war on me in rapid succession.  I didn't have the economy to hold them off while the seemed to be rolling in money.  My sovereign was winning all his battles but losing the war

So this was on easy, no way to maintain peace even after signing non aggression pacts and trade treaties.  And where can I find kingdom champs?  I got 2 in my first turns and then I met plenty of empire champs and killed them.  But didn't meet any kingdom champs in 200 turns

Here's my two cents. A few builds ago the AI was pacifistic. You could surgically declare on the AI one at a time without the others getting pissed off and just conquer at your own pace. Brad tweaked it so that when you do try to surgically remove an AI by declaring war, the others are like hell no, and mob the player. Now, I think the tweak swung the pendulum a little too far. They act a little crazy right now. I think Tuidjy's comments in this thread are spot on regarding nonagression pacts meaning squat, etc.

If Brad could just tweak a few things to make the AI more reasonable with diplomacy. My particular thought was if a player declares unprovoked war, big penalty. If the player does it again, HUGE penalty. And if a player's faction power is outpacing the AI, the AI is smart enough to team up (+10 relations with each other because player is outpacing) kind of thing.

So, in short, what I'm looking for is rational behavior. I want the AI to recognize I'm being sneaky and taking them out 1 at a time. Make them realize I'm full of it and team up. If I'm somehow top dog, make the AI realize they need to dogpile me. Right now, as Tuidjy mentions, if you're the bottom of the barrel in faction power it's like a pack of piranhas on a bleeding fish. Now I've been around for awhile so I find it challenging but if I was new to the game I might pop a blood vessel.

 I think it's just Brad finding the right balance - he's had the AI acting both ways. Gottta find that sweet spot in the middle.

Just a few other ideas. Balance or add some diplo penalties such as:

• Can't trust you because you declare unprovoked war - -5 or -10 or w/e value
• You're top dog and a threat - -5 or -10 or w/e value
• Another is top tog and a threat - +5 or +10 or w/e value
• Tweak the "you're at war with my friend so I'm declaring war" thing - dial that back, especially when two factions aren't friends but they declare war on the player anyway.
• Tailor the maniacal thing to sovereign specific. I would like a maniacal sovereign to be unpredicatable and crazy. It adds flavor to the game. But overdone it's crazy, especially to new players.

Again, I think Brad's almost there. Just needs some tweaks:

Nothing, confused Ts comments with willies

Another annoyance.. I'm getting +5 because im "dominating a faction".. yet a peace treaty is -5000 in value.. lol

Apparently dominating them doesn't make them more likely to make peace if their power rating is higher.

I think too much depends on power rating. Power rating is pretty much determined by pioneer spam. So either you spam cities for a high rating or you get everyone declaring war, even if militarily you can "dominate" them. Of course because of the power rating even if you are dominating them.. they expect you to pay an arm and a leg for peace. Of course even if they did sign peace they would just declare war the next turn because im still at war with another AI faction due to the dog pile mechanic.

@OP: I agree that diplomacy is still pretty random and downright confused in this game. 

IMO, SD ought to sit down for a good month to tweak and test the AI and actually play the game with nothing else in mind to figure this thing out.

Fistalis, NO ONE is arguing that AI is breaking immersion and doing stupid stuff. What you are saying was spelled out in my Karavox play-through in .982.  Around turn 132 I had an friendly AI declare was on me despite (1) having been bribed by me for a NAP 6 turns earlier, (2) being at war and losing to my enemy, and (3) being on the other side of the enemy from me. 

I thought that Brad listened, and toned down AI aggression.  I guess he did not tone it down enough at lower difficulty levels.  I am fine with it on ridiculous.

Now, we should still talk about HOW to fix it.  I think that at this point, the +/- values look quite good, but somewhere behind the scenes, the AIs ignore all the bonuses when they perceive weakness.

I think that if the player was the aggressor twice, everyone on the attacked's side is perfectly justified in attacking.  I also think that Empires dogpiling on a Kingdom and vice versa is fine.  AIs going against their allegiance is not. 

And finally, the greatest problem I have with the way AI declares war is that often there is no possible gain for them in it.  Seriously, if I have four cities and am already fighting four AI, what's in there for you to join in for?

What bothers me in all this is that the AI is not playing to win, it is playing to win against the human player.

Here's a scenario that best helps explain how I think the AI SHOULD work in terms of declaring wars:

A is strongest
B1 and B2 are second strongest
C is weakest
Let's ignore who is empire and who is kindgom, lets say all are kingdoms.

A decides to declare war on B1 to overtake its lands. Now, with the current AI B2 would probably declare war on B1 as it takes a hit on its power level from having to battle it out agains the stronger A. Especially if B1 is the human player.

BUT! If B2 really wants to win the game, it either needs to not wage war on anyone, OR wait for the armies of A and B1 get into action and then declare war on A, as it has its resources allocated to fighting B1. This is one of the few chances B2 has to overcome A and prevent it from steamrolling over it after it has destroyed B1.

This is how you win games against stronger opponents in Civs; you wait for them to declare war on someone and then declare war on them, hoping you can grab at least some of their ground and they're willing to call a truce as they can't fight on multiple fronts for too long.

What C should do is either declare on B1 to grab some spoils from the war with AvsB1 (B1 can't afford to focus on C if A is pounding on them), or just stay out of it.

That's how you play to win. B2 would gain next to nothing for waging war against B1, as they would lose troops against them and A could easily attack them immediately after he's done with B1.

I want the AI to play to win the whole game. If they're not the strongest player, they have to constantly look for chances at attacking the strongest one. If the human player is weak, then unless you can easily nab their lands and gain useful resources from it, it doesn't make any sense to wage war against him unless you are the strongest player and want to start destroying everyone one by one.