In single player games, FFA should be renamed as AIvH (AI versus Human) given the current state of the AI.
Case in point: a huge map game, 10 players, FFA, normal AI (random). I stayed alive for five hours, during which time I reduced one AI opponent to a neglible factor and had a decent fleet of 10 Cap ships and the usual small hordes, plus well developed military tech trees. However, then the 'rainbow' coalition showed up, a huge fleet of at least four AI players, all singing Kumbaya as they dismanted my systems.
In the post games stats, the only AI player that had been elimiated (after 5 hours of galactic struggle), was the AI that I eliminated. ALL of the other AI players showed steady growth that was above myself and the other AI player that I fought. This means that they were all happily co-existing with each other, happily making battle fleets that appear to do nothing except wait for the opportunity to pounce on the human player.
WHAT THE HECK? Where is the FFA struggle?
For comparisons, at least in Supreme Commander the AIs actually FOUGHT each other. I have yet to see AI players seriously attack each other, and I have played several FFA games.
No, I did not participate in diplomacy. But are you going to tell me that after five hours of game play none of the other AI players get mad at each other enough to attack each other? That they play the diplomacy game SO PERFECTLY that they never have a reason to attack one another? This is seriously unrealistic.
Yes, the diplomacy game should have some affect on how many AIs attack you, but you not be punished for not participating in diplomacy by having ALL of the AIs attack you, with NONE of the AIs attacking each other. Besides, the mechanics of the diplomacy game are flawed, right now you get demands from opponents from clear across the galaxy that should not even be concerned with you. In the CIV type games, diplomacy was something that you practiced with neighbors, but this game does not seem to have the concept of neighbors. You have AI opponents warping in through wormholes to come at you rather than doing the normal thing of expanding against their nearest neighbor.
As it stands right now, I will abandon FFA games with multiple opponents, and try various forced teaming options and see how that goes. I will also investigate turning off diplomacy all together and see how that works. Really, it is disappointing that the AI FFA behavior is not more reasonable.