Quarterback
Patrick Mahomes had what I consider to be the greatest start to an NFL career in history. He followed up his ridiculous 50-touchdown, 5,000-yard season in 2018 by throwing for over 4,000 in 2019 (despite missing almost all of 3 games). He certainly could have hit 5,000 yards in consecutive years otherwise.
His touchdown rate did fall from an astounding 8.6% in 2018 to 5.4% in 2019. Some of that could have been due to the nagging injuries, but more likely it is just typical regression toward a more sustainable level, as defenses schemed to take away the deep shots that were there often in 2018.
For 2020, I project Mahomes to fall between the two seasons in most ways, although his continued improvement as a player (physically and mentally) has also been factored in.
Projections:
The chart above includes my 2020 projection for Mahomes, as well as where he landed in both 2019 and 2018, for comparison. Remember, 2018 is a bit skewed because he only played in 13.25 games. Also, I have included YPA, which stands for yards per attempt, as well as the percentage of touchdowns and interceptions per attempt in parentheses after the touchdown and interception numbers.
These numbers in 2020 would almost certainly put Mahomes at the top of the heap among quarterbacks again, where I believe he belongs. The surpassing skill of Mahomes, along with the continuity of the offense and the surrounding cast, make these numbers quite attainable.