Brees had that pinpoint accuracy and anticipation, though. He didn't have the biggest arm, but he could still push the ball down the field until the end of his career. Gunslinger, but smart as hell with his decision-making. A leader to all of his team.
As for Big Ben? He had the big arm, had the strength of an ox, but he was basically carried to his Super Bowl wins (notably never won a Super Bowl MVP, losing out to his two receivers in Ward and Holmes - while his defense helped win him games), whereas Brees was the main play-driver on that Saints Super Bowl run and won the MVP.
Roethlisberger was not the absolute leader Brees was. Roethlisberger was not the gunslinger that Brees was; while he put up respectable statistics, he falls behind Brees in literally almost every passing category - and before anyone wishes to make the argument about coaches, he showed that he would've succeeded in San Diego as well, had they trusted his rehab.
He's simply not a better quarterback than Brees.
I’ll still never forget after his issue with the alleged rape of that girl and his bodyguard being and off-duty cop that Pittsburgh was so done with Big Ben that they offered him to the Rams for a 3rd round pick, but we had the first overall pick and were enthralled with Sam Bradford.
Big Ben’s personal team rehabbed his image, he married his long term girlfriend and Pittsburgh stood by him. This came out I think a year after we drafted Bradford.
For that reason as well as his needing to be carried, I’d say Big Ben had to go