WR Marquez Callaway, is he the final piece to the Saints Wide Receiver Puzzle?

I think you have to have one regardless, and I think Drew can still throw bombs, just not at the high accuracy/ball placement he once had.
And this likely being his last season, it would be good to get one on the team and learning the offense. Also, if Taysom really is going to get more snaps, he can dang sure zip it downfield. Same with Winston.

I do think that D. Harris can fill that role some, and TQS is fast for his size. But they're both 4.48-ish /40 guys. Which isn't true burner speed, but should be enough to get downfield some to keep defenses honest.

When the Saints signed Winston the arm strength of the QB room got exponentially stronger.

Teams don't respect or are not afraid of Brees throwing the deep ball anymore and it's shown the last couple of seasons. Even the 55 yard pass that Hill threw to Harris against the Vikings last year was a badly underthrown duck that if Harris would have been hit in stride was an easy walk in TD.

Winston might be able to push the ball down the field to a burner and he's the only Saints QB that is capable of doing it.