I'd wait to see what the entire picture looks like, or else you'll end up replicating your demise of Baltimore's defense predictions from last year. The truth is that even after all of the offseason threads and posts about how horrid Baltimore would be on that side of the ball due to their losses on paper, they actually got better by replacing them with an upgrade in talent in many areas by the time the season started.
I can't seriously look at Denver's offense with Demarius Thomas, Julius Thomas, Peyton Manning, and Wes Welker and claim that they're going to suddenly take a huge downward trend. They may not end up setting records again, but there's absolutely no reason whatsoever that they won't be one of the most potent offenses in the game still. Even if they would somehow lose 10 points per game average on offense, they'd still be scoring in the high 20's every game.
The loss of Decker and some OL changes are terribly overrated. Manning has the quickest release time of any QB in the game, and plenty of weapons left to throw to. One can assume that just about anyone can step in and be reasonably productive in Decker's spot with the other weapons that they have. On top of that RB Montae Ball was an awesome RB in college, and had been groomed all of last season to be the starter. He's a 2nd round pick for crying out loud.
