The amount of depth and overall flexibility of the secondary is what I believe will help. Other than the Dline not giving any QB pressure, some of our 31st ranked pass defense can be attributed to lack of real depth. When Glenn or Coleman went down, we had noone except for Wright to come in and contribute largely. Also Mcree didn't start until like the 6th game of the season and I think that was only after he was acquired by the team only a few weeks before that. Now we have a proven serviceable backup at FS, a very good back up at CB in Coleman should one of our CBs go down, and if our SS goes down we got Mcree and Coleman to decide from.
Now that you look at the options, this is a great move.
On our defensive line, I think last year will prove to be excellent experience for those that had to play last year.