The thing I think most people didn't consider was how bad Oakland was last year. Their top recievers were James Jones and Crabtree. Jones is killing it with Rodgers but who doesn't? He got cut from the Giants, he's bad. Crabtree is a #2 guy. Their rushing attack was hit or miss, and their defense, outside of Mack, was poor. For a rookie to have his TD:INT ratio with that team was incredible. Hell, throwing for 20+ TD's as a rookie is an above average year. Especially when you consider then being behind and teams playing the pass more/Carr pushing to attempt comebacks.
Now with a legit #1 WR rookie(who is only going to get better) and some more added defensive guys, they are a decent team. And you're seeing growth in Carr along with the team. Which is honestly the best case scenario. They may not make the post season, but if they can add one or two more quality starters through the offseason and draft next year, I see them grabbing a WC spot.