The forground was too bright in balance with the top half of the picture. I used the graduated ND filter to darken the bottom half of the picture. Thanks for the comment.
What did you use the filter for? I am not familiar with it. I think the picture is technically very well done: it's very sharp, colors are fine, the water is well rendered. The "thing" (waving straw?) in the bottom right is a little distracting, but not too much. However, the overall look doesn't inspire anything special to me. Maybe there just are a little too many things going on, giving a cluttered feeling or, more simply, the scene is just not for my taste :) Bye,Luca