I admittedly don't know that much about defensive schemes, so I would greatly appreciate more informed feedback here, but I wonder if Champ Bailey might be even more dangerous next year. Why? Flexibility, deception and unpredictability.
For several years, he was the best, and as such, opposing OC's could plan around him. They knew Champ would be on the same side of the field, and if not, he would be tied to wherever the #1 receiver lined up. That made him predictable. Smart OC's could (grudgingly, I'm sure) simply give up that third of the field, plan formations and route trees accordingly, and just avoid throwing the ball there. Champ's INT numbers have dropped in recent years, because opponents just quit trying to challenge him. They could also take Champ's great tackling right out of the play with a simple "go" route by the WR.
Might this change next year ... with potentially excellent results for Denver? A combination of age, injury, (alleged) cracks in the mystique and (especially) the other Denver DB talent, could make Champ's role far less predictable on any given play ... and make him even more dangerous. Will he be on the left? The right? In the slot? Even strong safety? He may have lost half a step (also highly debatable!), but he is still more savvy and experienced than 95% of DBs out there. I'll take that wisdom over raw speed, especially if deployed with some cleverness. Over to you, JDR ...
Crucially, the talent around him makes this flexibility even more potent. DRC has been awesome in man coverage, and Chris Harris can play inside or outside on any play.
I love to see Champ playing the nickel back, and I think he is extremely dangerous playing there more (though not exclusively). His exceptional tackling and play reading abilities become even more valuable in the crowded middle. Doesn't it actually make him more like a second strong safety in run defense and covering TEs and RBs (a clear weakness for Denver in recent years)?
Finally, an open question for more schematically informed than I: is it feasible for Champ to play safety on some plays? Or would that taking this argument too far?
All constructive feedback welcome ... Go Broncos.