I'm puttering around on Emperor now, and gave up on a Rome game after about turn 140 (Epic speed) because I was so clearly far behind. I couldn't manage a rush of any of my neighbors, because they were all too darned far away. Brazil and Japan were both about 25 hexes from my starting area, which in my experience means an archer rush will get there just in time to fail against city walls. My starting area had two small (5 hex) rivers. One river had a mountain. Which meant only two sites for Baths, and one for a poor (+1 science) Campus. There were 3 city states between my neighbors and myself. 2 Industrious and 1 Religious. All had their own little rivers. There was another continent nearby with Sumeria and Spain, reachable by galley. I tried peaceful expansion, and that went poorly. Beelining for Shipbuilding to hit the neighboring continent would have taken a long time. Maybe I should have taken out the city states? I don't often do that unless I'm Germany.