Differences between the difficulties?

I have seen the guide about the differences between the difficulty levels with regards to battle sequences (and start up funds), but I was wondering if there is a posting about, or if anyone knows the differences between the difficulty levels at the map level (i.e. diplomacy).

I'm not sure if we ever got anything official on the effects of difficulty level on strategic part of the game. In general though, that other factions get more aggressive.