So there's aggressive, defensive, economist and researcher (i think i got it right) - based on your play which ones seem harder to you?
Also, I'm curious if anyone found that matching a personality to the strenghts of the race helps making it a bit harder as well. I'm thinking for my next game I'll have at least one of each race and match them to what I see as their strengths. So TEC would use economist AI, Advent will use defensive, and Vasari aggressive AI. Of course it's possible that I'm simply wrong about their strengths, but assuming I'm not, what do you guys think? Has anyone tried doing something like that?