The boat in the background looks great. You may try resizing the house to just fit under the top border of your image. You could find moving it a bit more to complete this. The boat in the foreground...looks like a child's toy. Like wise the twig also looks more like a tree than beach wash. I also noticed the beach is very bright, after you've toned done the light source some, you may try playing with the material settings for futher brightening. Otherwise this has the makings of a wonderful render! = )