Re Killer. I always thought he wanted to end his career back at St Helens. Not that I'd complain if he stayed here of course.
The only thing that Tommy as a fullback doesn't have that Snake does is Brett's decade plus worth of experience. That knowledge of when to join the line, where to tell the defensive line in front of him to go, things like that. And at this stage I would think Snake also shades him with 1 on 1 defence (then again, Snake is probably the best 1 on 1 defensive fullback in the NRL so not being as good there yet is no shame for a 19 year old).
I think we're quite safe with Tommy at fullback, and he's only going to get better. The more pressing problem is who comes onto Tommy's wing? Wiliame isn't the answer, but are Goodall or Lavaka?