awsome stuff
some things I would improve:
light ray in the top left corner.. a bit too basic and not really necessary
the background clouds are too bright, seems like the rest of the picture is dull (really simple adjustment, but still)
be carefull of the brightness of the dark side of rocks in water reflection, doesn't make any sense to me
except for those, this is really gorgeous, honest. I can easily see that kind of art beeing in a film, like you were saying. I like it very much! wish I could do the same
keep 'em coming