As far as aerodynamics go you won't notice anything different with a fully sheeted wing. You will notice the excess weight that you added. And in my opinion only it makes it easier to cover. Now the downside is you will be adding plenty of unwanted weight. Now i know you won't think what's a couple of ounces. but as the sheeting gets farther and farther out on the wings the pendulum effect will come into effect. So it will be harder and harder to stop the snaps, spins heck even rolls or point rolls. thay will want to keep going and not stop when you let go of the sticks. An easy demonstration of this is grab an egg carton put four eggs in the middle and swing it back and forth in your hand. then move the eggs two on each side to the outer most point in the egg carton and swing it back and forth. you will feel a difference. now imagine that on a wing withh 55 inches. compared to the twelve or so of the egg carton. The tracer is a pretty strong plane as designed. if you really want to fully sheet the wings. you may want to explore lighter spar material. maybe with a strip of carbon fiber. to keep the strength.
Dennis