RE: aileron servo idea
If you plan to replace any part that looks weak to you, make sure to look beyond that weak part.
I've seen aluminum stock glued into a structure to reinforce it. With the metal glued to balsa that has little or no strength itself. That situation needed a layer of glass cloth instead of the aluminum stock.
If you're suspicious of the strength of your aileron servo installation test it. When newbies show up with their trainer for flight instruction the first time, I usually work the sticks while holding each of the surfaces in turn. I've found aileron servos that weren't strong enough, aileron hatches that were screwed into balsa, aileron hatches that were stong and wrinkled the wing covering (because the hatch support wasn't supported worth spit by the wing structure), and on and on......