If it is a wall hanging, seldom if ever to be washed, I'd say you're done. If there is any chance of it ever going into the washer you need more quilting. Check the batting package for a recommendation of how closely it needs to be quilted.
In addition your quilt will look better if the quilting is relatively even in density across the entire top. You don't want to have some areas with lots of closely spaced quilting and some with hardly any. (Exceptions to this rule of course).