Arden Key
The first name that comes to mind is Arden Key. The Raiders ranked last in sacks last season, and if Arden Key could have made a few adjustments, this may not have been the case. Key showed promise last season, and proved that he could get in the backfield, but unfortunately for the Raiders, Key could not finish the job.
Key missed out on multiple sacks last year that he should have had, but he either missed the tackle entirely, or could not bring the quarterback to the ground.
The Raiders selected Key in the third round of 2018, as he was one of the biggest questions in the draft. After the departure of Khalil Mack and Bruce Irvin, the Raiders badly needed a solid pass rusher heading into the season. Key did not produce at the level that they needed, as he lacked the size, strength, and moves off the line to live up to expectations.
Key has packed on 15 pounds of muscle in the last few months, and has been impressive so far in the off season. If Key can find a way to finish the job once he gets in the backfield, the Raiders pass rush will vastly improve all together.