Gaudreau has pretty well nailed down the 3C spot, and i'm ok with that. I could see him being moved up to the 2W is MJo gets injured, but i think that makes us weaker as a team. Freddy is at his best as a good defensive C with speed, FO's, and a bit of finishing skill.
Better off playing a Beckman or Walker as an injury fill in on the W, and see how they do. Both are offensively inclined.
I am having trouble seeing where Rossi fits, if he doesn't displace Hartman. He shouldn't be playing 3C over Fred, he will never displace JEE, and i don't see him as a wing. Playing him as 4C would just be silly...I think Dewar is more suited to that role, anyway.