Hmmm. Well, it's a good wallpaper.

I'll briefly point out the things that don't convince me too much:

- the clouds look too "solid". Maybe it's because of their perfect circular shape. A little more variety and irregularity would make the background richer. Still regarding the clouds, avoid using white when doing a sunset. Don't forget the clouds blend with the background color, so pick variations of such color and play more with their shading.

- I like how you detailed the dress but at the same time there's something that doesn't feel right about how you colored it. The source of light is supposed to be sun above, and if I am not wrong it's also in front of the man. So why his back is even showing highlighted parts and is in general so bright and shiny (I'm talking about the folds)? If anything, since the source of light (the main one) is in front his back should be really dark, and you might only want to highlight a bit of light around the his borders and around his shoulders since the sun's also above (and in front). You partly did this right (I can see how you made his clothes reflect part of the light's colour, good job on that), but his back needs to be way, way darker. There's almost no contrast in the terms of ligthting on him.

- The "cliff" could need a little a more detailing, also its shading needs to be more irregular.

And that's it. Heh, it didn't turn out that brief of a comment as I initially intended, but anyway I hope these pointers might still be helpful for you. Overall it's still a good job, it's just that it doesn't feel too polished of a work, yet.