[@Antarctic Termite]
[quote]-Should continents be larger and rounder? This will encourage overland travel a la the Silk Road and Saharan trade networks[/quote]
That's a good idea. It's nice to have some deep inland areas. In your current map, there's a giant inland ocean which could be filled in to achieve that goal.

[quote]-Should some landmasses be inaccessible to one another without sea travel? This could let us have fun with old-world new-world dynamics with two or three continents taking completely different cultural paths (until sail). Enough land in between would do this too, though (Mediterranean vs. sub-Sahara, Japan vs. Britain, see large continents).[/quote]

The current map already has separation into two continents, although the division is subtle: the only land connection between the east and west is over the north pole, which in most planets would be a frozen wasteland and thus a formidable barrier.