I think the identity (on the actual football field) will be largely the same defensively, and the offense will still lean on the run but to a lesser degree. Overall - it's going to be about whether this coaching staff can be competitive after the following "facelift." 

The run defense really shouldn't be that hard to fix if they find an adequate replacement for Dareus and do the right thing by moving Myles Jack positionally.
There are gettable free agent inside linebackers out there that should be able to play smarter more disciplined football against the run at the mike position.  Options in the draft as well, though they may require some seasoning.
NT/DT has two premier prospects in the draft and a few upper-mid-tier guys and free agents are available as well.

The secondary is fixable by taking an early pick at corner and adding a mid-tier FA to compete with Herndon.
(Folks are piling on Herndon for some reason right now, but he had 3 or 4 very good games last year,  struggled in a few others, and was solid in the remainder.  Personally, I think he'll make a great nickel when Hayden's contract is up.)
An upgrade at FS would be great, just not sure about any mid round prospects that could step in right away.
May have to wait to fix this spot unless they hit on a mid-late round guy or a cheap FA. 

Offensively - I'd love to see a tackle drafted, but they may give Cam one more year to audition more removed from injury. At the very least, they must add interior competition for RG at the very least and upgrade depth. 
Another TE into the mix is called for given injury and the unproven status of Oliver.
Should be able to get a steal at WR in this draft in the mid rounds. 
Mix in a CoP RB and let Gruden sort it out.

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