The only reason I'd re-sign him is to use him more in the passing game, which this staff seems averse to doing for some reason. Not a fan of him as an all-around RB.
But the real issue is this: With the new CBA there's very little reason to sign and pay a decent veteran RB. Rookie contracts are a fraction of what they used to be. And this is compounded by the fact that rookies cannot re-negotiate within their rookie contract (see: Russell Wilson. Seattle has their franchise QB for $600,000 a year for 4 years and Wilson can't do anything about it. It's madness). The labor is just so cheap now, and we're talking about a position that's the most 'interchangeable' between players. Draft a RB.