I also mostly play on epic speeds. Epic speed is 50% longer. If some goal is 'do this around turn 90' on standard speed, on epic it would be 'do this around turn 130-140'. So your NC should be before turn 200. I have a feeling you'd need to do it 50-100% better as you are doing it now. Large map: penalties are smaller then on standard size map (5% science/city vs 3%/city). But don't. It's a noob trap. Don't overexpand at start. Question: hows your world-wonderwhoring addiction?