The Butler extension conversation is probably worth another thread, but: Butler's also a rare candidate for showing loyalty to the Patriots organization that is measured in dollars - much like Brady, or Edelman, or arguably McCourty. He was plucked from obscurity because the Pats saw in him things others didn't, he was given a legitimate shot, played in the super bowl his rookie year and was put in a position to make a legendary, nearly-household-name-status play by a coaching staff that prepared him to an almost spooky level of precision.
The degree to which he has thrived in Foxboro over and above what he might have done in Random Franchise X is probably a bigger differential than for most other players. I can absolutely see him accepting a deal that pays him well, maybe a little below market but with more guaranteed money.