I predicted a fairly tight score but I think one factor we are overlooking is the New England run game. They rushed for over 200 yards vs Buffalo and are capable of controlling the tempo of this upcoming game against Denver's D-line. It all depends on how Denver plays us, but few teams are capable of playing the run well when they also have to defend the pass. The Pats double tight end set will create mismatches. If Denver gears up to stop the run we will pass and if they try to stop the pass we will run. That's really what bears watching, because if the Pats OL can dominate the run like they did against Buffalo, it will end up being a long day for the Broncos defense.
I think you are hitting on a key aspect of the game. The Bronco LBs are fast but not very stout. If the Pats can handle the Denver DL (a much less imposing group than they just faced) and get their TEs to the 2nd level, the Pats should be able to do well on the ground. The Bronco safeties make a lot of tackles in the running game, but I can't see them cheating up much against Brady.
On the other side, the key person is going to be Ninkovich. The Broncos run very well up the middle, but that should be muted with injury replacements (Koppen, Ramirez) going against Wilfork/Love/Spikes. Their other strength is getting around right end...which has actually been a bit of a problem for the Pats defense. If Ninkovich can set the edge effectively on his side, I'm thinking the Broncos will have a lot of difficulty running the ball.
(Quick aside...one of the most under-reported stories of the Pats season so far is how well Jones is playing against the run. His ability to stay effective regardless of the situation has been amazing...particularly for a rookie.)
These aspects become even more important if the weather is cool and wet. Consider that outside of the Atlanta dome game, Manning has only played in warm, dry, low humidity, thin air conditions at home. Even then, his longer passes have been anything but tight spirals. In cool, wet, high humidity conditions on Sunday, Manning may really struggle to get the ball outside the numbers and/or downfield. Brady's throws are generally unaffected by the elements.
All of this means nothing if the Pats don't have a gameplan to take advantage. If the Pats play off and allow Manning to complete 6 yard screens and slants at will, the result will look a lot like the Raider game last week. If the Pats press up and force Manning to throw through/over defenders, it will look more like the first half of the Falcon game.