Who can be the Kirk Cousins of 2016?

It might not have been enough to push his team past the Packers on Sunday, but what Kirk Cousins did in 2015 is nothing short of remarkable. Yes, turning Washington around into a playoff contender and inspiring the nation's capital to chant "You like that?!" at just about anything resembling a positive moment is impressive, but there's something specific Cousins pulled off that's truly stunning. Overnight, the unrestricted free agent-to-be managed to turn the biggest hole in his game into a pillar of strength. And in doing so, Cousins drastically changed the way we should perceive him as a quarterback.

Heading into 2015, Cousins had one glaring flaw as a quarterback: He turned the ball over. A lot. Over his first 407 pass attempts as a pro, Cousins had been picked off 19 times, good for a 4.7 percent interception rate in an era where quarterbacks throw picks far less frequently than they have in eras past. Pro-football-reference.com's indexed-for-era statistics suggested that Cousins threw interceptions more frequently over his first three seasons than any other quarterback in NFL history. An average quarterback would have posted an INT%+ of 100; Cousins was right below Ryan Leaf with a 66. Even if you don't understand index statistics, let's just say that being worse than everybody else and Ryan Leaf requires little translation. It was bad.

And through six games this season, Cousins was still that same QB, for the most part. He mixed solid days with performances where he lost the plot. With four two-interception games in six weeks, Cousins had thrown eight picks in 228 attempts, an interception rate of 3.5 percent. That was better than the Cousins of old, but it was still ugly enough to depress Cousins' value significantly.

And then, somehow, the clouds faded and Cousins saw the light. He brought his team away from the depths for a miraculous comeback victory over the Buccaneers -- yelling his now-famous phrase to cap the affair -- and never looked back. Over his final 10 games, Cousins threw 315 passes and was picked off only three times. He posted the league's second-best interception rate from Week 7 on, 1.0 percent, topped only by Tyrod Taylor. And over the entire season, Cousins' interception rate was an impressive 2.0 percent. He posted a 108 INT%+; after throwing interceptions more than anybody in league history through his first three seasons, Cousins was better than league average in the same category in 2015.

Cousins is a fascinating story heading into 2016, in part because of that massive improvement. If it sticks, he's a superstar quarterback, and there are reasons to think he could be that guy. He'd thrown only 407 regular-season passes before 2015, so it's not out of the question that Cousins could have played worse than his actual true talent level before 2015, and it's reasonable to wonder whether Cousins improved in a permanent, sustainable way with more playing time.

The flip side, of course, is that the struggling passer Cousins was in his first 681 pass attempts might be more meaningful than the breakout star he looked like over his final 315 passes. The truth is somewhere in the middle, but that's a huge swath of middle. If it's closer to the older model, Cousins is a borderline starter with a turnover problem, a poor man's Jay Cutler or Eli Manning. And if it's closer to the more recent edition, Cousins is a franchise quarterback hitting unrestricted free agency at 27, which hasn't happened since Drew Brees hit the market in 2006.

Somebody will make a very expensive decision on Cousins this offseason, but the truth is that he already has done something remarkable in totally reshaping the way we view him as a player. He took his biggest weakness -- a historically significant hole in his game -- and turned it into a relative strength. That's stunning and virtually unprecedented.

It's also fun to consider. If Cousins can do it, of course, other players can too. So that got me thinking: Let's run around the league and look at similar players who have other glaring problems with their professional output and wonder what their careers might be like if they find a way to improve on the weakest element of their game. I'm going to avoid players with truly intractable issues -- I can't make Darren Sproles 6 feet 5 or give Eddie Lacy a sprinter's metabolism -- but instead focus on tangible football skills that occasionally take a sudden leap forward, as Cousins did this season.

And let's start with Cousins' neighbor in the NFC East, a quarterback who is yet to conquer his biggest professional problem.

Sam Bradford, Eagles

Problem: Doesn't throw downfield frequently/effectively

For years now, the book on the former Oklahoma star has been that he can't chuck the ball downfield to his receivers. Over the past five seasons, Bradford has posted a 70.5 QBR on what the NFL defines as deep passes, which are throws traveling 16 or more yards in the air. That's 24th among 29 qualifying quarterbacks. That middling efficiency comes despite the fact that a Bradford bomb is a rare creature indeed; only 15.3 percent of Bradford's passes over that time frame have been deep passes, which is 28th among those 29 passers. Only Alex Smith throws deep less frequently than Bradford, and the Chiefs' starter is a far more efficient passer on short-to-intermediate throws than his fellow former No. 1 pick.

It was a major concern in St. Louis, and the issue didn't subside during Bradford's first season with the Eagles. Chip Kelly made a bet in acquiring Bradford that he would be able to fix the struggling Rams starter, and it was a bet that might have cost Kelly his job. You can imagine how, unafraid of getting beat deep by Bradford, teams pushed their defensive backs up toward the line of scrimmage and into the box. If Bradford scares teams deep, maybe the Eagles have an easier time running the football. And if the Eagles have an easier time running the football, Kelly's move for DeMarco Murray doesn't look quite as ridiculous. And if Bradford and Murray both look like worthwhile acquisitions, Kelly is probably still the man in Philly.

We don't know where Bradford will be next season, but his ability to throw strikes down the field with more frequency could totally change his future at the position.

Jeremy Hill, Bengals

Problem: Fumbling the football

This one might feel like a low blow after last weekend's playoff loss to the Steelers, when Hill coughed up the ball late in the fourth quarter and gave Pittsburgh a way back into a game that seemed all but lost. Even before that crucial giveaway, though, Hill has been having trouble holding onto the rock. During his first two seasons in the league, Hill has fumbled seven times over 487 regular-season touches. That ties him for the league lead since 2014.

Among players with 350 touches or more since 2014, Hill has the third-highest fumble rate in the league. He's behind only Adrian Peterson and Joique Bell, who aren't as defined by their fumble issues; Peterson is still going to get the ball and be great regardless of the fumbles, and Bell isn't going to offer much even when he holds onto the football. Hill isn't either of those guys.

If he protects the football, Hill is a powerful back between the tackles with the burst to accelerate into and through the hole for big plays. And if he doesn't, Hill is an enigma whom the Bengals will struggle to rely upon in key moments. They had no choice Saturday night, with Gio Bernard out after suffering a concussion earlier in the game. Hill simply has to change his habits to survive as a professional running back.

Eric Ebron, Lions

Problem: Dropping passes

Ebron is already in a tough spot because of whom the Lions passed on when they took him at No. 10 overall in the 2014 draft. Hindsight is 20/20, but amid one of the most talented first rounds in recent memory, Lions fans are already furious that since-fired general manager Martin Mayhew took a tight end and let the likes of Odell Beckham Jr. and Aaron Donald slip past Detroit's selection. Injuries ruined Ebron's rookie year, and he wasn't exactly healthy as a sophomore, but he did show flashes of the otherworldly athleticism that led the Lions to grab him in the first round.

The problem? Drops. So many drops. Ebron has dropped 11 of the 117 targets thrown to him by Matthew Stafford over the past two seasons. That's a drop rate of 9.4 percent. Nobody else in football has played each of the past two seasons at receiver and posted a drop rate in Ebron's ballpark. Not only is nobody else over 9 percent, nobody else besides Ebron even tops 8 percent. The next man up is Patriots wideout Julian Edelman, who has dropped 7.4 percent of his passes. Ebron might never make Lions fans cool with the idea of missing out on ODB, but he has to be steadier as a receiver to find a meaningful role in a Lions offense that could be without Calvin Johnson in 2016.

An oddity with Ebron and the drops: He has 10-inch hands (the same size as Beckham, for comparison) and was known to make impressive one-handed catches of his own in college. This is a concentration issue.

Derrick Morgan, Titans

Problem: Getting after the quarterback

Everybody agrees: Morgan should be a very good pass-rusher. Watch him on tape and you see an athletic edge rusher with the physical ability to break down opposing offensive linemen. As a run defender, Morgan has been rangy and consistent, especially when he lined up as a 4-3 defensive end before Tennessee shifted schemes. He has been a perennial breakout candidate waiting to happen, the league's next sudden pass-rushing star.

And it just hasn't happened. Through multiple defensive coordinators, scheme changes, and even now on his second contract, Morgan just hasn't become a meaningful edge rusher. He doesn't show the sort of steady pressure on opposing quarterbacks that often foretells future success, and his numbers remain a mystery. He has failed to top 6.5 sacks in any of his six professional seasons, including 2015, when he started with 4.5 sacks over his first four games and subsequently failed to record a sack over his next six contests before missing the rest of the season because of a torn labrum. The talent is there, but it's fair to wonder if the production -- and the consistency -- is ever coming.

Brandon Browner, Saints

Problem: Committing penalties

Nobody in the league is more of an outlier than Browner is in terms of taking flags. Since returning from a suspension during the 2014 season, Browner is the only player in football to average more than one penalty per game. In fact, it isn't really close. Browner has picked up 39 flags in 25 games, an average of better than 1.5 penalties per contest. The second-placed players, Bills defensive end Jerry Hughes and Rams offensive tackle Greg Robinson, each have 27 flags in 32 games. That's 0.8 penalties per game. Browner is nearly lapping the field altogether.

It wasn't always this bad. During his three seasons in Seattle, Browner had 33 penalties in 36 games. That's still among the league leaders, but it's not the sort of dramatic differentiator Browner has been since then. At the moment, he's fatally flawed, an oversized corner who struggles to run with faster receivers and lacks the nuance to get away with redirects on smaller players. And unlike offensive linemen, who commit many penalties that cost their teams only five yards, virtually all of the penalties Browner commits cost the Saints a new set of downs. If Browner's penalty rate dipped below league average, you could imagine him as a physical cornerback capable of locking down some of the league's modern, mammoth wideouts. Instead, he's one of the league's best offensive weapons and a first-down machine, albeit while suiting up for the Saints' D.

Xavier Rhodes, Vikings

Problem: Creating takeaways

Rhodes is another cornerback with a predilection for penalties, but he's effective enough as a cover corner in Mike Zimmer's scheme that the Vikings can live with his mistakes. What would make things better, though, would be if Rhodes could pick off a few passes. Through his first three seasons in the league, the former first-round pick has broken up 34 passes by either batting them up in the air, tipping them away or otherwise defending a pass in his direction. The only cornerback in the league with more passes broken up over that span is Houston's Johnathan Joseph. Teams target Rhodes frequently, but he comes up with plays.

What he doesn't come up with, though, is turnovers. Rhodes has only two interceptions for zero yards in three seasons. It's a crude measure, but the other cornerbacks in the league with 25 breakups or more over that time frame have turned about 24 percent of the passes they break up into picks. For Rhodes, that would mean we would expect him to pick off eight of the 34 passes he has broken up. Instead, he has two. Guys do make leaps in this category -- look at Carlos Rogers' breakout 2011 in San Francisco -- but they're often underappreciated by virtue of the lack of big plays. Rhodes may be heading down the same path as a pro.