Ranking the NFL offseason's 25 biggest position upgrades, from Brady and Gronk to a kicker

The bulk of high-impact NFL offseason roster movement is in the rearview mirror, and nearly every team was able to fill a roster void with a veteran addition.

Here are the 25 biggest veteran position upgrades from the 2020 offseason. Whether it was via free agency or via a trade, these teams' chances of 2020 success improved as a product of these significant acquisitions. Rookie impact is unpredictable, so first-year players were mostly omitted.

Note: 2020 team and player projections are my own, compiled through a thorough process that is both quantitative (league, team, coaching and player trends) and qualitative (projected depth chart placement and role). For all offensive linemen, I provided Pro Football Focus' player grades from last season.

1. Indianapolis Colts, DT
DeForest Buckner replaces Margus Hunt

Hunt's 2019 stat line: 17 tackles, 0 sacks
Buckner's 2020 projection: 62 tackles, 7 sacks

Colts general manager Chris Ballard said early in the offseason that the Colts' defensive scheme runs through the 3-technique tackle. He put his money where his mouth is not long after, trading for Buckner. The 26-year-old was arguably the 49ers' best player during a 2019 season that saw the team advance to the Super Bowl. Buckner's 7.5 sacks tied for sixth, his 12 tackles for loss fifth and his 61 total tackles ninth among interior defensive linemen. Buckner was a key acquisition for an ascending defense that includes the likes of Justin Houston, Darius Leonard, Kenny Moore and Malik Hooker. This unit is now good enough to help get the Colts back into the playoffs.

2. Tampa Bay Buccaneers, QB
Tom Brady replaces Jameis Winston

Winston's 2019 stat line: 380-of-626, 5,109 yards, 33 TDs, 30 INTs
Brady's 2020 projection: 360-of-573, 4,425 yards, 31 TDs, 10 INTs

In some ways, this one is obvious. Brady is arguably the greatest player in NFL history, and he has led the Patriots to six Super Bowl titles, as well as 17 consecutive seasons with double-digit wins. In others ways, it's not, as Brady is now 43 years old and coming off arguably his worst season, a campaign in which he trailed Winston in yardage, touchdowns and yards per attempt and was nearly identical in completion percentage and off-target rate. Believe it or not, Brady and Winston had the exact same QBR (53.7) in 2019.

Of course, little determines a team's win total more than turnover ratio, and whereas Winston infamously tossed 30 interceptions last season, Brady has 29 the past four seasons (60 games). Although Winston's 2019 interception total was certainly an outlier -- he hadn't surpassed 18 INTs in a season before last year's blowup -- Brady also edged him in QBR (often easily) in each of Winston's first four seasons in the league. Brady might not be as explosive, but he will help Tampa Bay toward its goal of reaching the Super Bowl for only the second time in franchise history.

3. Arizona Cardinals, WR
DeAndre Hopkins replaces Damiere Byrd

Byrd's 2019 stat line: 46 targets, 32 receptions, 359 yards, 1 TD
Hopkins' 2020 projection: 142 targets, 93 receptions, 1,143 yards, 7 TDs

Cardinals GM Steve Keim and coach Kliff Kingsbury were not shy about their interest in adding an impact wide receiver during the offseason. It's fair to say their mission was accomplished when they fleeced Houston by landing one of the league's best pass-catchers in Hopkins in exchange for a package that included David Johnson. An absolute workhorse, Hopkins has averaged a target share of at least 30% while ranking no lower than 10th in targets, receptions, receiving yards and end zone targets each of the past three seasons. The 28-year-old will operate as a go-to target for second-year QB Kyler Murray in an offense that includes Christian Kirk, Larry Fitzgerald and Kenyan Drake. Expect the Arizona offense to take a leap forward in 2020.