@K. Dog -- my armchair gm two cents worth
I understand concerns about the offensive line. I think the reality of attempting to upgrade multiple positions (or avoid downgrades with free agent departures) makes the OL a relatively low priority.
Other than additional depth (i.e., backups), the most likely position for an upgrade is center. Historically Belichick has not committed much of his available resources (a high draft pick or a lot of cash/cap space) to the center position.
In 2014 BB drafted Bryan Stork in the 4th round, but concussions ended that career prematurely. Dan Koppen was an 8-year starter after being selected in the 5th round in 2003.
For most of this decade the preference seems to be to develop an under the radar center. 2011-13 the position was manned by Dan Connolly and Ryan Wendell, both undrafted free agents. After Stork's rookie year another UDFA (Andrews) was the starter for the last two seasons.
Overall I thought Thuney and Mason played pretty well at guard. A free agent that would be an upgrade over either of them, or the two tackles would probably be too expensive to be worthwhile. At minimum the Pats do need a swing tackle to backup Solder and Cannon; right now the only options if either is injured are Waddle and Fleming.
Solder is heading into the final year of his contract. It would not be the least bit surprising to see the Patriots use an early draft pick on a tackle.
For the tl;dr crowd: there won't be a splash OL free agent signing. Expect a low-level FA to be brought in (remember Will Svitek from a few years ago), somebody we never heard of to compete with Andrews at center, and maybe a day one or two tackle in the draft.
