I personally don't like wallpapers that consist of a load of pictures simply merged together. I think you should focus on one or two pictures and make some more original content in addition to that. To me it also looks like the source images you used are of low quality, try finding some that aren't as compressed.

Your colour clash quite a bit too. Sometimes contrast can be good, that's true, but that green background in the second image just draws my attention away from the actual contents.