Very marketable, even. Your voice tells a story like the perfect voices can't. Paraphrasing David Byrne here, the more perfect the voice, the less believable the singer. I think your voice is completely good enough for this sort of thing, but more importantly, I believe the story you are telling.
That said,
please don't subject your appreciative audience to just two chords. Where's that confounded bridge? After one of your "f" chords, why not hang on a "g" for a while, then go back to what you were doing with the two chord two step. I think you need a chorus or bridge, and it should be really simple, too, but just sayin' . . . I know others will disagree . . .
a great song, man, and well sung.
-Tom