Would it be at all possible for you to use a different image of a dog doing something else.
As of right now the activity the dog is doing seems to be over-powering the entire sign....just a bit. Maybe just an image of a dog with a great big happy expression would do. A white dog might help to brighten the image a bit.
Also, try using Black instead of the Brown that is being used for the lettering and image of the back ground.