If Terry signs for 8 years, I would give him the C with 2 vets given the A to help him out. Over the next few years, start slowly phasing them out for new guys (McTavish, Z, Carlsson, whoever shows leadership qualities). Hopefully in a year or two, Terry is comfortable as the C. Then if you identify McTavish as the next best leader, give him the A and have a vet (Fowler or Killorn maybe?) mentor him as a leader. I like Terry with the C because he's the oldest of our new core and is very well spoken. I like McTavish given a leadership role because of the work ethic and dedication (not that Terry and others don't have it, but he just seems like a different animal when it comes to that). It's a great quality to build the new culture around.
Z might be a different voice for the other A (if he matures enough), he'd bring an energy and charisma the others don't have. It would be great to have that calming presence when needed and a guy that can energize the room if they come out flat.