Juwan is a guy (along with MVS) I'd love to keep under an otherwise new regime.....but the dynamics of player movement make it unlikely. Johnson has some serious untapped potential as an "F" (the newfangled term for a hybrid TE/WR). He's had some injuries, though, and of course some tepid-at-best play at QB since he's been here.
JJ has had some pretty bad drops over the last couple of seasons as well. He's really underperformed imo. He's got talent, but his execution has to get better and more consistent.