i think it looks good.
one suggestion i have for you is getting rid of the round rocks and find some nice rocks with character... like corners, holes, nice color. and try to make sure the rocks match each other in type and color. it will look more natural that way.
something tall would look nice to. notice how this picture looks better more natural then the one before it.
but i do like your start. i am also by no means an expert but these are just some of the things i have learned along the way.
Jeremy
