Fairley has done more than you think. 2011 injured rookie in a playoff year. 2012 had a nice season for most of the year. 2013 he was more good than bad for sure. He's not Suh, never will be, but he's a good player. 5.5 sacks is top 6 for DTs, Nick Fairley led the league in QB hits for DTs with 14 (same as McCoy), and 21 hurries was 18th. Plus Fairley was solid in run defense. He got knocked for penalties really. 2012 top 6 in sacks again, top 9 in Qb hits, top 9 in QB hurries and 7th best in run defense. He's a good DT with potential to be great if he put it all together.
Ihedigbo is very good in run support and on the blitz. Fits strong safety very well. Plus unlike Delmas, he's durable. He's a solid starter and the Ravens went cheap with cap issues. Age plays a factor for him with the Ravens letting him walk and switching Elam(1st round pick) to that spot(strong safety) means alot, doesn't mean Ihedigbo is a bum.
Jones when healthy did very well in 2010 and good in 5-6 games in 2012. 2011 struggled at DE with no DT help in Tennessee. He can excel on this line. Especially with the focus on Suh, Fairley and Ansah. He can be a solid stater.
Tapp can do what Idonije can. He's solid depth and worked with Washburn before.
Agree on Slay. Good starter potential big time. Bigger than the top CBs and faster than the top 3 CBs in this years draft. Mathis is still the depth as Houston is on the roster and could play. We are turning to him due to possible injury. Long way to go until the season for Houston. Houston in 2010-2012 form is a good starter for Detroit. At worst it's an unknown, let's not just assume he will be hurt and I won't assume he will definitely be healthy either. Unknown on the injury.
Carey did solid in 2012 at safety (gave up 38 QB rating, 28th ranked out of 88 safeties plaing 25% of snaps), sucks at nickel back in 2013 (other than Bears game). IAQ has starting experience with the Saints. Again got the job done in 2011/2012 at safety. IAQ gave up 21 QB rating in 2012 in 400 snaps. He struggles against the run but the Saints didn't have the hogs up front that Detroit does. Could upgrade with a rookie still too but experience might win out.
LB depth is unknown. Let's see any of those 3 filling for an injured starter. And really we just need one of the three to step up (unless 2 starters get hurt). I would think any could fill in for Palmer for sure. Tulloch/Levy bigger shoes to fill but let's hope they stay durable like last season and Tulloch all 3 seasons.