Hi Andy, and welcome to the Guild. Although we have more than a few cartographers here who specialise in 'real world' cartography, most of us approach mapmaking more as an art than a science. If you would like a load of professional opinions in addition to any information you get here, you might want to try posting your question on www.cartotalk.com which caters to people who do real world cartography for a living.
All the best
Ravs