hmm it looks okay. and now since u want my real opinoion, heres what i gotta say:

improve blending- it looks like u just slapped a render on a BG
put some lightin in would ya
put some more fx
kill those brushes
use burn and dodge tool

btw im just tryin to help ok, i dont want to hurt anyones feelins or anything. i dont think this is bad at all, i just think u have more potential