Following on from what Gidde and Ascension were saying, I'm with the 'too dominant coastlines' school. I think the usual convention for rail lines is that they are black (with or without little cross lines), but it's just a convention. Would it make any sense (any relevance?) to capitalise the lettering for capital cities? Or maybe distinguish the dot in some way (e.g. make it a square?). If capital cities have no 'in game' relevance, then I guess not.