What I find exceptional us the fact that BB the GM traded Bledsoe (in the division), traded Seymour, traded Branch, traded Vrable, traded Moss, traded Mankins, released Milloy, released McGinest, let Wilfork walk, let Welker walk, let Revis walk, let Talib walk, let Vinatieri walk...and you know what, it turned out he was right every time.
The few guys who stayed their full careers, like Light, (Troy) Brown, Bruschi stayed because they were willing to play at the Belichick price.
BB has resuscitated many careers, including guys like Corey Dillon, Harrison, Ayers, Revis...and created stars out of trash heap guys who history would have forgotten, otherwise, like Ninkovich, Dion Lewis, Welker, Woodhead, Vrabel, Izzo...and turned undrafted guys into household names, like BJGE, Malcom Butler, Andruzzi.
I think it is a mistake to judge BB the GM based on his batting average, because talent is a hit and miss thing. His technique isn't to make every single pick count. His technique is to take advantage of opportunities to improve the team, scout everyone, look under every stone, and kiss a lot of frogs. He is panning for gold, and digging through a lot of gravel to find it. Batting average may actually be quite low, but the results speak for themselves.
The best thing you can say for him is that when he sees a diamond in the rough, he recognizes the upside and nurtures it. Jamie Collins was a "who?" draft pick. Cassell, Edelman, David Andrews, Tom Brady, Matthew Slater, Stephen Neal. Takes some imagination to see the potential.