Up forward. Maybe give him the odd burst in the middle, but like saj said, the goal sense and defensive pressure are very important in the 50.
Also, he's still small in comparison to other midfielders in the league, we don't want him getting crushed.
Certainly up forward where he has to be accounted for by opposition teams, while used intermittently in the pivot and on and off the bench to hopefully keep other coaches over-machinating defensively.