R.e. Shadows:
If it were me doing the map - and its not of couse - but just saying.... I would map it with no shadows and then work out the rough heights of the map and make a 3D model with just the rough shapes in it and then render out a black and white shadow map. Id then blur it a lot to give it soft shadow which I know is not accurate to a sunny day but is more like cloudy day and then apply that to the map. I can apply the shadow map in ViewingDale so that it darkens the relevant places. But of course the more accurate you want the shadows the more accurate the 3D model and if it were me then Id not make it all that accurate and just live with it. But then my maps are nowhere near as good as everyone elses and maybe other people would want to have better shadows that it would provide. But by doing it this way its consistent - and as a bonus you can render out several shadow maps for different directions or different times of day.