A shapeshifter.

Barring that, I'd probably want to be what I call my Soulform (different from my fursona) or one of my fursonas. My soulform doesn't have eyes, ears, a nose, and has only minimal tasting capability as well as extremely thick plating (think crocodile but about two inches thick, or more in certain places, so no real fine sense of touch), so it has next to no stimulation from the physical plane, and no useful stimulation, but sort of makes up for it simply because it's huge and muscular and has decent ability to see with its mind's eye.
But, I think to avoid stirring up attention of a military sort, I'd probably go with my fox fursona. But, since I can, I might toy with the idea of a masculine herm. *shrugs* Maybe.