While it is possible that someone in the future "may" be a greater QB for the Saints, there are only 1 or 2 QB'sin the past that could possibly be considered for this spot. And since none of them got the Saints to the Superbowl, let alone won it, Brees is the man for this list.
I know that everyone else on the list has already completed their playing time with the team, but I say "so what?"! Put Brees on the List!!!