Shifters, AI, Infected and Drakes all specifically say, in their descriptions that they CANNOT ever acquire resonance. Sapient critters do not have this explicitly spelled out. I still beleive that the prohibition against having magic and resonance, (which appears only in the qualities description, by the way) is meant to be applied to the qualities that grant it, unless specifically stated otherwise, as it does in the entires in the SC for drakes, AI, Infected and Shifters.
Where did you find the "small target" advantage? I don't see it under the pixie description anywhere...
Peter