Thank you all for your kind words and advice on the mountains. It motivates me quite a bit.

So the next step for me was to detail the coastline and to add the rivers.
Take a look at the result.

I'm not so happy with it. Especially in the northern region, I feel that the whole relation between the rivers and mountains is quite messy and its not clear at first glance what is mountainside and what is river. I mean, they are difficult to seperate.
Do you people feel the same? How can I improve and make the rivers "pop"?

As you can see, I also changed the Shape of the Crater and also added the island with the gigantic tree. The new chape of the crater is supposed to symbolize the area where the meteor went down and surfaced the earth. In the southern part just below the central island is going to be a big nasty swamp made out of mushrooms and shrubs.

Click image for larger version. 

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