I voted ruckman as post Simmons we have a huge gap. We saw what happened in 2007 when he was injured (Tucky rucking was an indictment on the list mangement and recruiting). Both Patto and Gus have question marks over them and Putt is a long termer.
After the ruck we need a full forward. I doubt Hughes will make it (talent does not guarantee success). Other forwards in Riewoldt (CHF), Connors, Morton and Brown as small forwards are decent.
Outside of that I think we have most positions covered with Schulz, Thursfield, Moore, Newman, Raines and Sanchez in defence; Lids, Foley, Cotchin, White, Tambling, Tuck, Johnson, Edwards and Richo in the midfield.