Definately Miller. Dunn will be a half forward flanker. Miller is coming along nicely, he is a great physical presence much in the same way as Jonathon Brown and Barry Hall. After what happened to young Tommy Lonergan i don't think people will be running back into Big Bad Bustling Brad's space any more. So my answer is Miller by a mile.
Miller is a natural CHF although I think he should be given more chances out of the goal square. Maybe he will when Neitz retires, but I think he has potential deep in the 50.
Dunn looks like a naturally gifted player and could player any role up forward I reckon. He is a pretty good kick for goal so he could be full forward.
Johnson is a big meat axe and will reek some havoc when he gets fit in 2007. Him and Jamar rucking and alternating up forward (Jamar took a few grabs against Geelong) will be very dangerous.