Agree 100% Texwood on AG's chances at the next level. Hence, and I suspect you agree, why he is a late round projection or perhaps UDFA. His best "fit" at the next level is likely as you said in a 3-4 outside at DE. The NFL has zero film of him playing that role. He's been inside in a 4-3. And, the question marks around his knee do not help either.
He seems like the kind of guy Belichick would love if he isn't drafted. I'm hopeful 1-year-in Skins GM Scott McCloughlin, who is VERY good at what he does, will take a shot at AG.