think nothing more can be done in this pic. all a question of the moment you release the shutter: the sun's position in relation to the clouds, the shape of the clouds, how the light reveals their volume, shape, folds, etc. and the reflection. The silhouette is OK. In this pic too much sun, so too burning a sensation.
So suggest u shoot again, and take many shots. 1 good shot in 20 is not too bad i think.