One thing missing is detail in the whites. And as rexbobcat pointed out, the image does not have a lot of variation in color or tonal values between the elements in the shot...it all sort of blends together. I also do not like the way the whitewater looks rather greenish-blue...I dunno...the lighting before sunrise is so,so "flat"...I think it's actually better to wait until the sun is higher, and to shoot then, and then revise the images to look more like this...
Is that cheating???