If Tomlin, as you state, has "taken over the defense", then tell the class why Butler is still here. It can't be because he provides some intrinsic defensive genius, since, as you state, Tomlin has taken over the defense. I assume that means all aspects of the defense, since you're plainly stating that Tomlin is doing the play calling and drafting the players for this hybrid defense. So Tomlin is doing all the defensive scheming, coaching, personnel calls, etc and Butler is mere eye-candy as a "disciple" of the 3-4 defense so yinzers have a clutch throwback to cling to? I mean, no offense, but that's absolutely cross-eyed retarded. You're saying that the Pittsburgh Steelers are employing Butler for absolutely no reason than to be a fall-guy for Tomlin. A million dollar pinata. I just find that absolutely ludicrous to believe, or even to entertain such a far-flung idea.
As for my tweeks to the defense, I, nor anyone else, would know if it would work. But it would absolutely put the most athletic LBs on the field. Which is what we should want. Don't come back with "Durpee couldn't stand up to an OG or C", since he's not blocked 100% of every game by the LT exclusively. Moving Bud inside would give us some athleticism there, and give us the absolute ability to blitz from all four LB spots. Which, as we saw under LeBeau is why the 3-4 was so successful - the QB wouldn't always know who was blitzing and who was dropping back.
Additionally, I don't see any suggestions from you other than "Fire _____". Firing someone without having a viable candidate to replace that person with is a sure sign of future failure.
I will agree that one game doesn't make a defense. Nor does it prove that a defensive scheme is an exact blueprint of how to play going forward. However, we did put more pressure on Brady than I ever recall. We also were able to pretty much hold the Pats in check. Now, that can be attributed to Brady being older (though his stats are still great) and Gronk not being the Gronk of years past. But, Brady still had Josh Gordon, Julian Edelman, Chris Hogan and James White. He's done more with less talent than that.
I will also agree that the 3-4 as it is being ***-****** now is not working. Not in any means, even though statistically it's "ok".