re: What kind of QB style does Brian Kelly actually want?

Based on his decisions so far Kelly and Denbrock believe that turnovers, fumbles and interceptions, lose football games.
Certainly not a new concept in years past. However when offenses are regularly scoring 45+ points per game, a turnover that results in a 3 or even 7 point score is not insurmountable.

I think that J Daniel's " regression" in the passing game and his reluctance to throw ths ball over the middle is due to a constant barrage of Denbrock telling Daniel's that under no circumstances will the ball be thrown unless the receiver is wide open facing Daniels.
Under no circumstances will the ball be targeted between the hashmarks.

That explains JDs fear of throwing the ball downfield.