Interesting, I'd consider Pring at CB allowing Roberts to play LB with Mehmeti lhs, play Bell rhs attacker and Wells in the middle.
But, I guess you may be right that Naismith is moved to CB.
Naismith for Williams should be a no brainer, better passer and Williams on a yellow.
Bell at CF was tried twice last season by NP, and neither time worked, not worked in fist 45 today either.