Quitch said:
I tended to play the AI, but my favourite ever game was from the demo, when it became a 2v2 with only a single sector in the centre of the map linking the two halves of the galaxy. Ah, the wars that happened there... 
I remember playing games like that in the old OS/2 Warp version of GalCiv. Those were quick and decisive games. I enjoyed GalCiv in those days, but the AI was, and still is in the demo of the latest version, a little simple. You play for a while, and you discover the thresholds that will keep the AI from becoming angry, yet still allow you to ramp up production when you want a war. SE4 isn't like that -- the AI is too psychotic to let you get away with it.