This year has not shown any of that. If your lesson from this season is that QB was the biggest issue then I am not sure you have watched the correct games.
We have had serious issues at every level and on every unit except maybe the secondary and ST. The QB is just one of the many puzzle pieces that didn't execute. But his performance is connected to extremely inconsistent pass protection and skill position players that drop passes or are not where they are supposed to be.
Similarly, the performance on defense is highly affected by the fact that most teams could just run at us whenever they wanted. What is the point of having players like Winovich or Butler if they only get a handful snaps each game because we are way too rarely in 3rd & longs ? This also automatically devalues the worth of our pretty talented secondary.
Getting a DT that could stabilize the run game the same way someone like Wilfork did would be a much bigger relative improvement than any QB you will be able to get at #15. Most of those QBs who will be available at that spot will still be available in the second round and maybe even in the third (that is if we had a third round pick and it wasn't forfeited thanks to Kraft Media).
QB and a 3 Down DT are of equal need. Whether via the draft, free agency or both. At DT, I'd been looking at Jaleel Johnson, Larry Ogunjobi, Maliek Collins, and Johnathan Hankins. QB, I'd be looking at Brissette, Winston, or Sudfeld. There will probably be others, but they are just speculation at this point (Garappolo, Carr, Mariota, Mullens) What they want to do is match up their Bridge QB with similar skills to whomever they add if they don't feel Stidham is the guy. Fitzpatrick would be a guy who I think could be a good #2/#3. Certainly better than Hoyer proved.
I disagree that there are serious issues at every unit. The RB unit is extremely deep. Harris, Michel, and Taylor are excellent young players. The WR play this year has been better than they've been given credit for. It was their play that made Cam's completion % look respectable at 65.4%.
The pass protection was excellent for most of the year. The exception was when Wynn was out and the Pats put Eleumenor at LT instead of Herron. Eleumenor is a liability on the left side just as Newhouse was last season. Eleumenor is average to good at RT. Honestly, as I said in the post game thread, I felt that Thuney moving to center would be a huge upgrade over Andrews.. Andrews was abused last night.
I don't know who made the decision to put Eleumenor at LT, but he played poorly there each game. It's why I don't see the Pats bringing him back. I can see a team needing a RT shelling out decent money to add him.
I also see another team adding Andrews. As much as I love him, Thuney is just the better player. And yes, I'd pay Thuney 15-16M a year to be THE GUY of the Pats' O-Line. I believe that the run blocking and pass blocking would be significantly upgraded. I think I've seen Thuney fail to pick up a late guy once. And that was because of how Andrews called the blocking assignments.