I agree with you on some points. He is hitting well. Really well in fact and he has been really fun to watch. He does need to draw more walks, but I don't think that is completely his fault. Everyone in the league knows that he is not going to hit it out of the park. Knowing that, I think many pitchers are just challenging him by throwing strikes. If he keeps up this kind of batting average, pitcher will probably stop having that mentality and he'll start drawing more walks.
I also agree, he shouldn't be in RF. But, I don't think that they should move Span either. Span is great in center. Revere is good too, but if you watch them you can see that Span reads the ball really well. Revere doesn't read the ball as well as Span, but he makes up for because he's so damn fast. I know this has been said before, but Revere would be best in LF. His arm wouldn't be that much of a problem there and a LF/CF combo of Revere/Span would cover a lot of ground. It is Willingham that needs to move, not Span.