It's slowly gelling. What I think I'm after is a map which a DM can hand his players and which they can pore over. I'm begining to think that for RPG purposes it's almost the lack of information and tantalising clues which make a map more exciting and says something of the information the mapmaker had to work with. This map looks (to me) like it's been drawn by someone from say, Jartor or Baladum whose knowledge runs out over distance.

Anyway I think that's where I'm going.