So turn 24, computer has agro'd some trolls that have attack 120, oh look straight to my main city, game over.

Im playing on normal and this seems to be the general trend.  Also not happy about how you cant place cities in any spot, nor am I happy with the fact that the computer can scout you completely, it should be that you should put an open boarders like civ.  currently they just walts right through you're territory and late game this can get quiet annoying trying to keep track of everything.