OK great question, the answer today is the offense.
But... after Seymour returns our D will be far better (than it is not now)...IMO.
Fact is we possess an unheard of combination of the best of both worlds and lead (top 5) on both offense and defense.
One thing tho, take a look on Miguels salary page and count how many players are in salary years. (Moss,Stallworth,Bruschi,Wilson,Gay,Seau,Mitchell,Paxton,Gaffney,Washington,Izzo,T Brown,Alexander,Wright,K Brown,Britt,Woods, S Thomas) ok subtract the ERFAs but we could lose a lot of talent in FA?