Oh No! The "Leekies" have gotten into your head.
One of my favorite sayings is that "Life is about perspective." In the days of yore, we built 1/2a kits that were 1/8" slab sided with doublers! These tanks were built to survive the appocolypse. Into these we squeezed another 6 to 8oz of the era's radio gear. Then we took these 1 1/2 to 2lb behemoths, stuck a cox baby bee on the nose and tossed them in the air. They flew!
Today my radio gear with servos, battery, and reciever weigh about what one of the old servos weighed. If I hear someone speaking of lightweight covering it is usually for a 16" span micro electric. Over the years I have covered with tissue, silkspan and silk. Painted too. In the last 10 years I have covered all my 1/2a planes with Ultracote. I goes on easier, has less chance of warping the wings, and is 3 to 4 times stronger so if my plane bounces around a bit in the car or on a less than perfect landing I don't have to fix holes. Is it heavier? Yes, but in weight measured in grams. If it is that critical you need a bigger motor. In this case a Norvel .074 would fly that plane fine with the old gear. If it worries you, spend $11 for a 400mah battery from Radical RC and save 2oz! That's enough to cover crashing the plane six times and rebuilding sections with epoxy and lite ply and still be under weight! Spend more time flying and less time covering!
Just my 2 cents.