Thank you for your feedback

@ jbgibson
I tried to work with saturation and shadows as you suggested. Here is the result:
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@mozltovcoktail
I used render->clouds for water and render->plasma for land.

I hadn’t much time lately so there almost no progress. Only placement of terrain and outlines of buildings. I wanted to have two versions of the map, colorful and printer friendly but it turns out that it is too easy to accidentally change layers and I would need to redo half of the map. Is there an option in Inkscape to change every color but black into alpha?

Click image for larger version. 

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