I like your atmosphere colours, the composition feels good. I'd be tempted to put in a few more notches in the smallest scale of your cloud density fractal, to make your sky a little more dramatic and 3D. Then I'd like to break up your ground some with a smaller displacments dotted about. I'd also want to work out why those palms don't look as if they live there, and by that I mean (and don't know without giving it some research), what would be on the ground around them. Eg, dead frongs, smaller plants etc. Are palms really that reflective? What would be their tint colour in that light? Would the reflection be that sharp? Or more diffuse?
Lots of things to play with here.