Hemispheres and Big_and_Small are great, interesting map types; I've regressed to Pangaea though (natural coastline, naturally) because I know I won't need a last ditch transport-building effort to take out Willem's cultural powerhouse from across the sea. That and there's more chance of war in Pangaea; in other map types threats from AI on another landmass are pretty idle. Also, tactical nukes are far more useful in Pangaea! So yeah, that's it really.