I don't mind it when the AI notifies of certain tech upgrades. I don't mind when the AI declares War, or asks for peace. I only mind because the AI does all 3 of them very close to one another, plus each other AI doing the same.
The AI also doesn't have combat objectives (capture city x), or (weaken factions army/military score), or (faction x is getting too big). Nor does it trade in a future directed way. AI won't ask you for crystals/metal/horses for the purpose of building X units and launching an invasion under said (capture city x).
AI doesn't realize when it should stop an invasion because future cities could be the downfall of the faction, which happens all too often.
The AI needs to perform both diplomacy and warfare with advanced intentions behind the actions. It shouldn't surrender to Player A because it declared war against 4 other players and is losing to Player B. Instead, it should only declare war on Player A when it isn't already in war.
Sometimes, the AI will sit around at war with each other, doing nothing. Player A will then declare war against Player C and fully commit, causing Player B to finally send everything against Player A. Player B and Player C will not form a strategic alliance against Player A. Instead, they will declare war on each other because they both think the other "looks weak" at a specific moment in the sequence.
