I am almost finished with covering Bad Axe. Here I am sticking on the tissue strip stiffeners I use on just about every non scale plane I build. Particularly if the design is a little floppy, like most embryo wings. tomorrow, I will apply a set of the strips that go in the opposite direction in each rib bay. Than I will pin down the wing with any warps I want set, and shrink the strips. Then cover in the usual way. It stiffens the wing by a very large factor, and makes the wing much less likely to develop unwanted warps with a tiny weight gain. Too little to fret about.
Try this, you will like it.
OK, this just might be 'tip of the year!' (roll it into next year)