In all honesty I wouldn't be shocked to see the Sox not get overly involved in the FA market. Outside of the usual "reclamation type SP", and maybe someone like Abreu on a 1 or 2 year deal, when ultimately the price tags for Bay and Holliday go too high for comfort. Next off season is the off season you could see the Sox make a splash in the FA market so to speak. Namely Joe Mauer(if available of course).
The Sox could spend some dough still though. As in contract extensions for Beckett and V-Mart. I know your thinking " but you just said they would try and sign Joe Mauer". But after next season the DH/3B(or 1B) spot becomes available. Which V-Mart could slide into, making room for Mauer behind the dish.
I would imagine that if the Sox are to bring in any big name player this off season, it will be via the trade.