My feeling on the Pohutukawa Tree, is to possibly bring what appears to be the grass on the lower left our further to help balance your creation, maybe as far as the grey color in the sand. Also something in the upper right. I feel that it would balance your creation more.
You see I am a photographer. One of the rules I use, is called, "the rule of thirds." I try to create a photograph that uses this rule, that will attract the viewer, and give them a feeling mellow comfort. Maybe that is something you might wish to add in your creations. Hope I have been of help.
Oh and keep'm comm'n