I'm not an expert at this scale, but several years ago I was researching for a postal plane called the "Grace". It was designed with the Cox .049 engine in mind to keep costs down as well as using an easy to run engine. People who built copies found that it was a better plane when built lighter. Meaning, some models built were not the lightest and suffered in their flying ability. Since the conception of the design, smaller, lighter servos and batteries have become plentiful, and at pretty good prices. So, with that in mind, I'd recommend servos in the "sub-micro" range, like a HS-55. 8g/ 16.66 oz-in. I don't think I'd go Nano, unless you use one for the throttle. The "Grace" was designed right at the cusp of some of this lighter technology. Again, remember these suggestions are my opinion, and I would hope others more experienced at this scale would chime in.