Well, just on the Patriots defense, you have the following players who are, or have been, starters, and are second round draftees and lower, going all the way down to 'undrafted' status:
As for the "studs" determination, that will, naturally, depend on your definition, but I'd say that's a pretty darned good group of players.
Well, only half of those guys were drafted by BB / Pioli. Hobbs and Samuels are very solid picks as 4th and 3rd round respectively, Gay is an undrafted gem, but I wouldn't exactly call Wilson or Sanders a steal.
As the team gets stronger and stronger, I think it makes perfect sense to trade draft picks that have little shot to make the roster, at least for another year. We have a young enough team where we are not mortgaging the future if we continue to trade a draft pick here and there for mature, proven players who can fit.