
This map reflects a little bit the spirit of the books - Melnibone is an impenetrable fortress, and the only successful attack was launched be Elric from the Southern Continent. Melnibone used magic & their dragons to control the rest of the world, but had become so decadant, inbred, and complacent that they had very little military left. The island nations controlled much of the wealth through trade and had most of the power, which is why they connect to nearly every continent, but the continents do not connect to each other.
Mostly, I think these variations will make for interesting and different game play, which is half the reason you want to make a map in the first place.