This.
My preference is for back lines to be split into a couple of broad units. 9, 10 and 12 are the playmakers with 11, 13, 14 and 15 as strike runners. I love petit general scrum halves like Morgan Parra, Dimitri Yachvili and JB Ellisalde who do as much playmaking as a flyhalf. I like flyhalves who are as adept at attacking the gainline as they are at controlling a game with their boot. As such, I like a safety valve extra playmaker at 12 who can take pressure off his 10. With playmakers at 9, 10 and 12, there should be plenty of room created for the outside centre, wingers and full back to attack the wider channels.
In short, I prefer creative 12s who'll think about passing the ball to bosh merchants who have no peripheral vision and never pass the ball.