Breaking the rules, the focus point is in the center. The space to the left gives room for the viewer to imagine the wave creeping up to the rocks and leaving the gifts it carries. A rock pointing to the focal point brings the viewer back into the photo were the portion of a plant is left draped over the rock. The cherry on top.
When doing a painting it is often a good idea to study the details to make magic happen. The tree from a distance seems to be gray, but when looked at closer the other colors seen bring light and shadow. Texture is created and interest added with the reddish brown shades you see in the closeup of the bark. Daniel Smith Quinacridone Sienna watercolor might be a good one to use to add a spark to a watercolor painting of this tree.