Your eye liner looks a bit haphazard to me. Maybe retouch it a bit? I dunno...the thumb over head overlap--I have no issue with that whatsoever. To me, the overlapping of the thumb adds a three-dimensional depth cue. I just got back from a shoot down by the Columbia River, in blinding sunlight off the water, my eyes feel like they are bleeding, so they might be playing tricks on me, but in the grunge-look image posted above, your nose and the bridge of the nose have a kind of odd, white, pasty-looking tone to the skin. I might go wayyyyyyy over the top on this grunge-like effect, and go to some kind of a preset look, like Matt K's Lightroom Killer Tips' "Ultimate Fighter" look, medium or strong, and realllllly make it look grunge. The grunge effect looks pretty good on the hands and the one arm, but again, your nose just looks pasty, for lack of another word. I agree with you not being quite sure about the grunge version; it *is* I think, a step in the right direction, it seems to coordinate well with your expression, the clothes you have on, and the hand gestures, but I'm not 100 percent sure if it's the exact right processing look for this shot.
As far as the lighting setup used for this: it might have been ghetto, but it looks VERY good in terms of results. The eye catchlights, nose shadow, and the shodows from your head and arm show that you were close to the wall or whatever, and it adds a good 3-D shadow effect , that's subtle, yet "there". REALLY good lighting work, I think, no matter HOW you achieved it!