Diplomacy..a bit pointless?

[Colovion]

I've read that thread and it is very helpful up to a point. It still seems as if the computer still doesn't think long term or thing like a real person (not that I blame them, they are an AI faction..) but it seems to me that diplomacy is like this:

Lots of options to offer/demand but the AI diplomacy seems to still react the same way with the on/off switch - still very clumsy to figure out what they're thinking or how they COULD think these things such as "Stopping the fighting? That's a joke! We will not rest until every one of you is dead" Meanwhile they have one province with half a stack and you have three stacks waiting to invade. You'd think they would say "oh yes, please! Let us trade with you!" But it's always the same thing - even when your 7 Influence Diplomat is talking with a 0 Influence person....

Lots of possibilities - but it doesn't seem like it comes out right in the game...