The problem with Carter is the same as it's been his entire career: he takes more than one season to acclimate himself to a defensive scheme and be effective. The first year in a system he doesn't trust his knowledge of the scheme enough to stop thinking and just play. Once he gets comfortable he's pretty damned effective. That said, I would consider him for a cap friendly deal. He's already familiar with our scheme and a full off-season back in the program should get him right back to speed.
He'd be a depth signing, at best, but I wouldn't hate it.