Classic Patriots choice in a number of ways:
Easley had no combine or pro day numbers on him at all. This discouraged most of the NFL from looking at him.
Easley has explosion for his weight class. His 3-cone numbers (if Easley had any) shouldn't be compared with Wes Welker's combine numbers, but for a 288 pounder he's quickly outside or inside on an offensive lineman. Stunting around some other defensive lineman to find an open corridor is part of his game.
The comparison to Gronk is fair. Gronk had a back issue. The Patriots took a risk.
No guarantee that Easley will start in September. BB is known for drafting guys that wind up on the PUP list, and so BB squeaks a 54th guy past the September 53 man limit. By late October one of the starting 53 players has landed on injured reserve.
Easley's job is to lay back his ears on passing downs and go, often up the middle where passer disruption counts the most. He doesn't need a year to get up to speed, unlike many positions. There's a chance that, with his explosion, he can occasionally drop into zone coverage.
BB really needs a pass rusher in Peyton Manning's face. Manning's numbers go down when he has to scramble.