There's a ton of stuff that could be done with this, if I could have my way with it. My first advice, I guess, would be to make less actual structure, and imply more of it instead. You don't have to draw every strand of grass on the ground, every leaf on a tree and every brick on a massive castle wall. It's harder to do and it's confusing to look at.
It's better to imply the shape of leaves on a tree through color and shading. You could imply the shape of bricks with color variations and mere highlights, maybe a few cracks.
Then, as sharprm said, it could really do with an obvious lightsource. As is now, things don't really cast shadows or have highlights, which makes everything look very flat. And on top of that, you've got a very strong saturation on most of the picture, which also contributes to that flat feeling. And then there's the pillow shading, of course, which is a terribly bad thing. No shading at all would look better than pillow shading. What you really need to do is sit down with one of those statues, decide a light source, and figure out where the light would and wouldn't reach. Then, apply that to everything in that picture, and your character. I suggest you start with the statue, actually, because it's not too small and has decent outlines already.
Heh, basically, I like the potential of this, but I'd like to see everything remade from scratch. I could probably write a full essay on what I'd like to see done and how to go about doing it, but I don't have time for that I'm afraid...