I agree with J.Edward - I think you have a really cool feel to the map here, like we are looking down on a real world from above. I love the terrain as it is, without the linework. Way to go keeping all the mountain shading consistent with the local perspective, by the way! But the coastlines are a little incongruous, as are the graticules on the globe. (That's not to say they're bad, it's just my opinion!)
Maybe you could try lowering the opacity on the coastlines, if not removing them altogether? The graticules might be fine with lower opacity. I think the rivers are OK because they still look like part of the image.
Another thing you could do to really push the satellite view is add specular sunlight glints on the water and include some clouds. THere are lots of photos from the Space Station you can rely on for inspiration, such as this one.
Of course, my suggestions are going in one direction, but others are fine, too! Are you planning to add more map features on top of the image (cities, roads, etc)?