first one is my fav as well.

In all cases I think you should play more with lighting, figure out where your render/stock is getting its lighting from an borrow ideas from that, try out the filter/render/lighting effects. Play with the layers an opacities an see what you come out with, thats a good start ^^ Nect light play I would suggest is adding colour to your tags and use them as lights , a good way I do this is usually with the c4d/fractal im using steal some colour from that or my render and lightly dust areas with the colour an play with the layer

hope I gave you some tips that might not have known about ^^