What are you looking in a "best layout"?
Turn 148 victory. Same as the previous post, by turn 147 no other civ islands.
Got a turn 158 victory. By turn 157, there were no other civ islands. Pretty nice start, only setback was a 80 cliff island that worked as a bottleneck.
The earliest i could win the game is turn 189. Has anyone gotten a better time? (I know it depends of the inital layout.