I have nothing bad to say about the offense that Kubiak has created here. For that, he receives 50 gold stars from this fan.
My problem with him stems from what I consider to be a lack of ability to detach from the playcalling duties on game day, as well as what I think is a lack of week-to-week tweaking of the game plan he builds for each Sunday's opponent.
I truly believe that Kubiak is so confident in his system and in his players on offense who run that system, that he thinks his system and his players can beat opponents without having to do any extra work on tweaking the game plan. And the emergence of Arian Foster has only furthered, IMO, this sort of arrogance within Kubiak's mindset.
So it leaves him scrambling all game long, trying to figure out how to adjust to what the opposing defense is doing, and he finds the answer in the second half of games. Instead of having a few backup plans in his back pocket, it appears he's going into each game with a casual, laid back attitude and approach to the game...then the fit hits the shan and we see what happens from there on out.
I just don't think he wants to be the guy I envision a head coach to be: The guy watching the action on the field, evaluating what his players are doing right and what they are doing wrong, watching for patterns on the field and thinking of ways to exploit them, actively coaching up his guys as much as he can. Instead, it seems like he's far away and consumed by playcalling.
Just my two cents.