Wilfork. No question. They’ll have to rebuild the tight end position as a Gronk contingency plan. Vollmer and Mayo should be fine and back to form. Tommy Kelly would be a big plus as well.
All four together will really elevate this team. But Wilfork is the queen on Belichick’s chess board and if he’s back and as effective as he’s been, he’ll almost singlehandedly fix the run defense.