In 13 years, Teddy Bruschi had 30.5 sacks. Teddy was a great LB for the Pats, but 30.5 over 13 years is hardly a stud pass rushing ILB.
As for outside pressure being overrated, you are incorrect. A stud OLB applied outside pressure on every passing play, he has to be accounted for in the offensive scheme and that overrated outside pressure forces the QB to throw the ball sooner than if there is no outside pressue (see the Patriots highlight film from 2008, 2009, 2010). Let's look at thar dreadful playoff loss to the Ravens, the pass rush was in Brady's face early in the game, it even scored a touchdown on a sack. It was in his head for the rest of the game, in the offensive line's head the rest of the game also.
There is nothing wrong with wanting the Patriots to take a pass rusher, some people believed that it was their biggest need in the draft, but taking a tackle that by all accounts needs a lot of time in the weight room before he can actually play at the NFL level qualifies as a "project". The Patriots pass rush sucked! When it needed pressure it couldn't generate any. The only time it came through was when Cunningham pressured Manning into that interception, proving my point. Outside pressure changes the game, contrary to what has been posed here, the Patriots do not apply inside pressure. Mayo had two sacks last year, and 175 tackles. Spikes had zero sacks, Guyton had three sacks. So, all of that vaunted inside pressure, they totaled 5 sacks for the year. Add that total to Ninkos and TBC and you get a decent pass rushing OLB.
If the Pats cannot generate pressure from the edge this year they will not go 14-2 again, the DBs will get tourched again, they will be near last in third down defense again and near last in opposing QB rating again. It is rocket science, and Belichick's defenses aren't all that sneaky anyway, he uses formations and substitutions.