I wasn't suggesting a Sandoval + WMB platoon. I would probably go with a Francisco/Holt platoon. Holt is already going to be on the roster, and can play super-sub if necessary. Middlebrooks and Cecchini would start in the minors, and if either ends up ready to take over, they can.
Platoons are always painful on the roster spot, but we no longer need to worry about the Gomes/Nava spot in LF. I'm willing to cut ties with Craig, the guy looks done. OF is Cespedes, Castillo, Mookie. Bench is Nava, Vic, Holt, and whoever they sign for backup catcher. If Cespedes is willing to play RF, this team has many versatile players that can move into a variety of spots. Nava at 1B/LF, Vic at any OF, Mookie at any OF and 2B/SS, Holt in the infield.
Just to be clear, this is only a strategy I prefer if the Red Sox go spend 300 million on Scherzer + Lester and need to save money. If they sign McCarthy and Masterson, this strategy is not acceptable.