Jeff Green simply does not have the ball handling skills to be a 2 guard. After the point guard, the 2 guard should be your best ball handler. He has inadequate ball handling skills even for a small forward, which is why he has such a difficult time creating space to get a high percentage shot. His offense consists almost exclusively of 3 pointers, foul shots, and transition baskets. I would bet the vast majority of his points come from those 3 categories.
You make a good point, but I think we could easily get by if our next SF had solid ballhanding skills (Parker, anyone?). I am already quite comfortable with KO (and to some extent, Sully) at the PF so that is a bonus. I also think Green may surprise some people if he is exclusively a guard. His passing ability, while unimpressive in the NBA, was one of his prime skills coming out of college.
I get that as careers progress, players usually move from SG to SF - not the other way around, but Green still has killer athleticism so it's worth a shot. If we are looking to be at least a 2nd round playoff team next year, I am in no rush to get rid of Green, unless [of course] he is part of a package that brings in a superstar