Preliminary thought:
Using Dennard and Talib outside with McCourty as the FS should give the defense more ability to use cover 1 man defense, letting Chung play more in the box, to his strengths.
Secondary thought:
With this front 7, do the Pats even need Chung up there, or are they better off using two more free safety type of players (McCourty and Gregory)?
Either way, I definitely want McCourty at FS with Talib and Dennard at CB. The SS spot is up for grabs with any Chung, Gregory, and Wilson being an option, and I think both Cole and Arrington have a shot in the slot.
As I wrote on the Aqib Talib thread, I think that the deep FS is perhaps the most important position in the secondary. It's no surprise that many of the better defenses in the NFL have had good FS play. Ed Reed at Baltimore has been the standard of course, but Ryan Clark has quietly allowed Troy Polamalu to freelance and get away with it. Dashon Goldson in San Francsico and Earl Wilson in Seattle anchor their particular secondaries and make them very, very solid.
We haven't had anything even remotely resembling a decent deep safety since BB cut Brandon Meriweather. That's the #1 need for the secondary IMHO - a guy with the range, vision, ball skills, closing speed, processing capability, instincts, tackling ability, selflessness, discipline and communication skills to guard the deep part of the field, coordinate the secondary, and make everything work. Meriweather had most of the physical tools to do the job, but he was too undisciplined and selfish to play that role effectively for BB.
James Ihedigbo, Sergio Brown and Josh Barrett obviously couldn't play that role. Pat Chung undoubtedly has talent, but not for that kind of role. Tavon Wilson has shown in his brief career that he both has talent and that his talent isn't particularly suited to that kind of role. Steve Gregory has not shown that he has the talent to be a full time starter in that kind of role.
In contrast, Devin McCourty has ALL of the attributes of a great deep cover FS that I listed above. I think he could be as good as Earl Thomas and better than Goldson once he gets used to the position. It may take him the rest of this season to get adjusted, but he's already been a big improvement over what we had before. McCourty is a very good zone CB, but if we're playing press-man CB it doesn't really play to his skill set, and his skill set is perfectly suited to the deep FS role.
I think that you start with a "basic" set of two outside press-man CBs in Talib and Dennard and a deep FS in McCourty, and then adjust from there depending on health, opponents, scheme and number of DBs on the field. There may be times you want a "Big Nickel" package with 2 out of 3 of Chung/Wilson/Gregory. There may be times you want someone like Gregory playing more of a FS role, with Arrington or Cole in a nickel role. There are lots of options to build on once the core is in place.
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