Just a point, if I may butt into your discussion.. There is NOTHING wrong with being an average player in the NFL. 90% of NFL players are "average". I think though "average" is another way of saying "equal". Don't forget in this age you not only have to be a great football player on the college level, you have to be an extraordinary athlete, just to GET to the level of "average" in the NFL.
James White is an EXCEPTIONAL receiver at the RB position. If he had gone to another team that didn't use him in a way that allowed that gift to be emphasized, and forced him to try and be a between the tackles runner, then his career might have been a lot less successful. But that could be said about a LOT of players in the league. Being in the right fit is a key for most players. BTW- James White, like Edelman, is ANOTHER one of those Pats players who is an overnight success....years in the making.
KVN is another player where fit AND time mattered. He was on a bad Detroit team for 3 years just trying to get to be a starter. At the time he was traded he was almost an afterthought. He gets into "the right fit". Add 2+ years of experience "in the system" and you have a guy who many consider the best player (so far) on a really great defense.
Just a thought