I like all your points, except I disagree with #3.
Brady can get the ball out quickly, but that line buys him so much time!! So many Sundays I’m looking at him taking his time, and I’m screaming that no DLs are breaking through the line. When he wants the time, it’s there. As opposed to our OL which collapses quickly
When you look at the schemes given, Brady's "time" breaks down into clear silos.
One silo is when the defense is playing defending with 7 or 8 guys and only rushing 3 or 4 guys. Typically, the OL has the advantage of double teaming one or two players, and if the offense keeps in a TE, maybe as many as 3 guys get double-teamed. That's not winning with blocking, that's just shooting fish in a barrel, so of course Brady has time. One of the primary reasons that the Patriots run game looks effective is because they run against 4 and 5 man boxes with all pass defenders behind them, so those OL are simply taking what the defense is giving them. Smart.
A second silo is when the defense blitzes, so it's sending extra men. When that happens the Patriots RB's are good at pass protection, so they execute their blitz pickups well. In those situations, Brady can throw the ball away, and doesn't hesitate to do so if he thinks he might get hit. This is why Brady doesn't do so well against pressure. But, the scheme that Josh McDaniels runs tends to pick up and compensate for pressure pretty well. Also, as you mentioned, the offense is designed to get the ball out of Brady's hand fast, to minimize the effects of pressure. So pressure can be effective, but with quick WR's getting open and a hyper-precise thrower of the ball, they can still move the chains when there is pressure. But, that requires a QB who can maintain that hyper-precise throwing. When you throw a lot of short passes, your stats look artificially good, but the chances of turning the ball over actually go up, despite the INT per throw going down drastically. Brady is the best in the league at avoiding INT's. Again, this is highly dependent upon a QB who is not only accurate, but consistently hyper-accurate, and very few NFL QB's could run this, much less rookies.
The third silo is massive pressure, overload blitzes or jail-breaks if you prefer. This is when the defense puts more people in one area than the offense has blockers, assuring that they get a rusher unblocked into the QB. There getting the ball out quickly and accepting throw aways is all you can do. Brady doesn't go long a bunch in those situations, he stays safe and gets the ball out, if the play is there, he makes it, if not, he throws it away.
Yes, Brady has a lot of time to throw, and yes that is the basis of how he can stay good and stay healthy. But it is the defense being unable to affect Brady more than it is the defense being unable to affect the OL.
If you look at the defenses that dominate the Patriots, it's not ones that bring pressure necessarily. Moreso, it's the defenses that can apply super-tight coverage on the underneath routes, like the Falcons in the Super Bowl before they inexplicably started playing Prevent Defense and gave the game to the Patriots who wore them out with death by a thousand cuts of short underneath throws. If you can clamp down on those underneath routes and prevent Brady from having an open guy in the short patterns, that OL isn't good enough to consistently stop pressure no matter how many guys you bring. But if you let those short route receivers like Edelman get open, Brady is going to kill you with his hyper-precise passing, and it doesn't require an OL to block for almost any time at all.
