The gap is not really good, and it may or may not cause some flutter, most likely in the ailerons. Turn the wing upside down, flex an aileron so that it hangs down, and lay a 1/2" wide piece of scotch tape down the hinge line, or iron a strip of Monokote in the hinge line. Do the same on the stab hinge line. This will stop the problem. And your ailerons and elevators will be more effective as well.

Clarification: the tape/Monokote is down IN the hinge line, in the shape of a "V". This allows the control surface to flex normally.

Clair