A Rodgers was a franchise QB while he was at Green Bay. There were more than just the Jets interested in his services, it was the Jets that were the highest bidders. He got more than Brady on the open market.
Point is, it's a team sport. Good QBs can be on non-contenders.
The idea of moving Diggs this offseason after moving on from Davis would not be smart. Replace Davis and worry about Diggs next year is just such a smarter strategy. The cap hit is less, and the progression makes more sense. Lets see how our first rookie does before penciling in major minutes for two unknowns.