There's a lot of room on the spectrum between very bad and very good. Yes, calling them "very bad" seems way over the top, I think even bad is a bit harsh but wouldn't quibble- personally I'd say they were a mediocre team, held back by a terrible coach.
Not sure why you think their defense looks improved, it's their O-line that took a huge leap (on paper at least).
I honestly don't think you're paying very close attention- you said they had "no" running game when they were a little below average, and say they were always trailing when that wasn't even close to reality. You keep taking pot shots about the teams he beat, but he had them leading for almost the entire game against KC, TB, and NO (2 of those on the road), 3 of the best teams in the NFL, and he played great in them. It's not like he's racking up garbage time stats against scrub teams like you're implying.
Pro bowls are pretty much meaningless, and I'm not necessarily making predictions about next year or the rest of his career as anything can happen. I just think you're way off base on how impressive his rookie season was and the circumstances around it, and his ceiling is as high as just about anyone's because he was so good last year under less than ideal circumstances. Anything can happen with injuries, new coaching staff, etc., but yes, I'm very high on him.