Regress
Steelers - Lots a lot of veteran leadership is gone. Hines Ward, James Farrior, Aaron Smith, Chris Hoke. Harrison and Polamalu aren't the game changers they were a couple years ago. Todd Haley is a fiery change from Bruce Arians as offensive coordinator. Not sure Big Ben and those young WR's get along with Haleys strict style.
Hard to imagine they won't slip
Saints - This one is obvious. Lost their head coach and play caller. Interim head coach is even suspended for 6 games IIRC. Some players may be seeing suspensions also.
Will probably contend for a while then fade away
Chargers - Lost Vincent Jackson. Rivers had a down year last season which isn't a good sign. Could he see a McNabb-like fall from grace? Defense isn't getting any younger. This team consistently fails to meet expectations. Could it be that they just aren't as good as people thought they were?
I think you are a few years late to this party
Progress
Bengals - Andy Dalton and AJ Green are the real deal. The defense is solid. They have 2 picks in the 1st rd of the draft too.
Dalton is decent, but there are many better QBs than him to consider him a reason they would be an elite team. Their track record of being good back ot back is atrociousl
Bills - Too much talent on that DLine to not be effective. If they can stay healthy, the defense should see a big improvement.
They added a good DE and a journeyman who will get exploited by the run. Name value yes, contender, not so much.
Eagles - Hard to see them being any worse than they were last year.
They were bad because they were chokers. Not sure if they have made changes that will correct that
Lions - Stafford to Megatron is developing into an unstoppable force. The Lions should continue to progress unless one of these guys has a big injury. Suh will redeem himself after a bit of a poor sophomore showing.
I see last year as them peaking until I see more. Epitome of top loaded team who pay boatloads of money for a handful of players and have nothing left to surround them with
Colts - Andrew Luck is better than any QB that started for them last year.
Better player, but as a rookie won't play much better than the collection of slugs they trotted out last year
Can't Call It
Bears - Cutler and Marshall had great chemistry in Denver. This finally gives the Bears a WR threat that they've seemingly lacked forever. They should be better this year, but its hard to say how much they'll progress since they're in a tough division with the Packers and the Lions.
Interesting team. Cutler seems like a QB that will simply never win. Each year there will be an excuse (OL, weapons, defense, etc) and in most of them he will figure out how to be 8-8
Jets - Can they be worse than they were last year? I don't know. Rex is a good coach. I think it depends on their first round pick this year. Do they add someone that comes in and makes an immediate impact? How does Mo Wilkerson develop in his 2nd year? Their D seems like it's 1 or 2 players away from being elite. But the Tebow/Sanchez thing has huge potential to cause distractions. Basically the same crap as last year, but now with Tebows always popular name thrown in the middle of it. Possible QB controversy. Locker Room could implode. This one is hard to predict. I think they'll be better than last year, but not as good as they were in those 2 seasons they made the AFC Finals.
The Jets severly lack talent. They are a 3-13 team plus Revis. Aside from Revis, Mangold, Harris and in some opinions Ferguson, it is very difficult to find a player on the roster that is above average for their position. No WRs, RB is mediocre, DL is weak, no LBs aside from Harris are worth much. Safeties stink, and of course QB is a disaster. Without Revis the D that was 20th in points allowed WITH him would be totally exposed and the offense already is.
The above is all just my humble opinion. Preseason hasn't even started, and the draft hasn't been done. Lots of things will happen from now until September. Hold outs, Injuries, trades, etc....