You pretty much nailed it with the second paragraph, except for Chung. Bodden and Branch are borderline--could be high 70s or low 80s. Stroud? 70s for sure.
I think the 80+ players SHOULD be: Brady, Welker, Gronkowski, Mankins, Vollmer, Warren, Wilfork, Mayo, Bodden, Chung, McCourty, Meriweather, Gostkowski, Mesko, and Katula (they're including LS in this game, right?). That's a total of 15. They're probably assuming Matt Light remains on the team, but I think he'll walk. They're probably also giving 80+ ratings to Green-Ellis, Branch, Hernandez, and Koppen. Maybe Stroud, I don't know. I haven't paid attention to him since the mid-2000s when he was relevant. What was he rated in Madden 11?