A Great Image, but the only and main critisism is the articial look due to the perfekt shaders etc.
Besides the wet look paper and the human Skin Table, I also think you can mostly enhance the look of your paper!
Besides changing from Tokio Hotel to some proper Artist, I would'n let the paper look so perfekt. Try instead of the bump map some subtile deformations (maybe displacement), they catch light & shadows better than a bump, at the corners the paper coud be bend upwards a little etc.
I would also try some very small and subtile bump Map on your paper.
But the Pro way would be a very, very subtile blend between a very light phong and a diffuse material. check out
this tutorial for the technique!
Also you could try to use another little more reflective shader for the inked parts of the paper, but the gain should be also very subtile!
Your instrument shader looks also to uniform to me. Try adding a exponnt Map for the bumpy parts using he bump map to get some more organic look & Feel for this mat!
Some subtile aditional lights to generate some interestings highlights & reflectons + shadows could be worth a try too
