Loving the whole orb idea, I especially like the fact that there is a definite centre to the world too, the gateway between the oceans! I take it there's a canal there, an a hefty price to pay to use it!
The antique map is brilliant! How did you get the concentric rings in the seas? I've tried to do something similar but it always ends up looking very poor, as opposed to the crispness of those you've created.

J