Thank you for your comments.
As I was writing the post, I knew that my map has a major flaw, it didn't really have a purpose. I was just trying to see if I am able to create a 3d/oblique/relief map with the tools at hand: free dem downloads, MacDem, POV-Ray, Photoshop, Illustrator, on a Mac. I agree with your comments, as I was asking myself the same questions.
Map Media, this is how I made it:
1. crop, color adjustments and heights in MacDem (an old little program which only runs in classic)
2. export to POV-Ray
3. view set-up, color and heights fine tuning, rendering in POV-Ray including a layer with a mapped image with roads, hydro, ...
4. photoshop layers for towns, hydro, color correction, ...
5. photoshop file placed in illustrator, traced roads, type, scale, ...
So now, the question is: are there better ways, more appropriate software, but again, I only have a Mac.
Best,
maphattan