Why would Rico be only a red zone target? He looked pretty fluid on routes in the seams. It's hard to argue against his hands. And even if he's only a red zone target, what a target he is. Doesn't that help Zeke and the threat of red zone running if the defense has to dedicate at least once beefy guy to Rico? Some teams have figured out that if the TE goes a little wide, he doesn' need to block his man very well since he's already out of the play if you run. That's the bulk of the Patriot running game plan.
Rico's blocking may need work, but if Linehan is all that he can figure out a way to work around this limitation.
Or they stash him on IR. Though that could have Leary-like effects.