Maybe I am giving too much credit to OCs here, but I think the gameplan they use is very much predicated upon what their offensive personnel is and how it can be used to best exploit the team they are facing. Now, once the game starts and points are being scored there, changes will be made accordingly. You obviously don't want to just pass the ball when playing with a lead, and vice versa.
I also don't think it's fair to say the Ravens aren't a team that plays to their strengths because of how they used one player last year, and they actually did get away from the ZBS to a degree when it was obviously not working.
I'm going to disagree with your take because Kubiak has clearly made changes in the past based on his personnel. When Schaub got hurt and Yates was the QB, the number of passing attempts went down dramatically. Now that's an extreme difference, but it shows that he is willing to change the focus of his offense because of personnel. The same thing happened last year, but in reverse. The RBs were hurt and ineffective and he gave the reigns to Schaub/Keenum. Is that because they were always losing by a lot or because their RB situation wasn't pretty? They did lose a lot of games, but it's not like they were getting blown out of the water. There was no reason to completely abandon the running game like they did strictly because of the game situation.
In regards to your projected numbers for Flacco, they don't look right to me. You have him at a 60% completion rate which is inline with his career, but he should be attempting a considerably larger number of high percentage passes in the WCO. I would be shocked if his percentage is that low, and I also can't see his TD/Int ratio being that poor.