Your first point is a strong one. No real argument to be made.
The second point is at most a partial. While Brady isn’t tremendously mobile in a big way, he is generally enough within the pocket if he isn’t injured. But more appropriately, he is much less likely to be baited into a quick dump off to the defense. Manning has been particularly subject to that - especially in the playoffs.
Even that caveat would still leave a balance towards the Seahawks...except for the overt stupidity of the last week.
Last year the Seahawks would not have been in the Super Bowl if not for Sherman batting the ball away from Crabtree in the end zone. This year the Seahawks would not have been in the Super Bowl is not for Green Bay self-destructing in the last 4 minutes of the NFC title game. They have had a lot of help, especially this year. Arizona playing without their quarterback lead the NFC West the entire season, and when Seahawks played them they were on their 3rd string quarterback. Then Seattle was only able to clinch homefield on the last day of the season because of an Arizona lost. This is not a great Seattle team and if they manage to win the Super Bowl twice in a roll it will be because got every lucky break in the world on the way, especially this year.