One thing I've found intriguing but havent seen discussed much on here is Wiles and Foster switching the d-linemen from end to tackle and vice versa and back. Everyone knowing all 4 positions can be nothing but a positive from a depth standpoint and allows the coaches to get the best 4 out there at a given time.
Wiles talked about adapting to the philosophy of the NY Giants dline and the success they've had with interchangeable linemen who just wreck shop from any of the positions. Granted, Bud's "30" defense which I understand he developed with Gregg Williams didnt exactly pan out back in 2010, but I love the NFL influence and our coaches' willingness to evolve. I am so excited to see this D on the field this fall.
QBs of the ACC beware.

Comments
TG doing the same thing with the secondary. Basically we will have a D of interchangeable parts. Builds artificial depth and allows for in game adjustments/scheming. Should be very helpful against offenses like GT, UNC, Clemson.
The only thing you need to make sure of is that you have the "big boys" able to play their true positions when needed against more physical D and Olines like SEC/Michigan/Stanford. Can't be putting an end at tackle and making him try to out-speed an OL that is full of athletic 300 pounders. Need to man up there.
I think we might just be able to do all that this year if folks stay healthy. And if Van Dyke and Tweedy can split time at Whip and stay nasty and fast.... oh boy. (No offense to JGW, just don't see him in that equation given injury and history. But I do think he can be a special teams ace)
As a defensive-minded fan
I see some things coming out of spring practice that get me pumped.
Mixing it up
Makes the D less predictable. The O cannot figure out match-ups quickly enough before the snap. The QB can't figure out who has a weak match-up or who to check off to because of movement and switching around. All this assumes everyone is healthy and experienced. When you lose depth it becomes more difficult.