RE: how to sttrengthen without adding weight?
Forget about the carbon tape, just get a 2 oz. bottle of both thin and medium C/A, carefully soak all the joints with thin C/A until you see slight pooling, keep moving fuselage around allowing the C/A to flow everyplace, then spray kicker. work small areas at a time until all areas are completed. Next go back over all non gusted areas with medium C/A, kick and your ready...
Bob