The Steelers choices to me are more about defensive playcalling philosophy. Do you try to mirror whatever the offense is doing to minimize poor matchups or play the down and distance? It would seem to me the Steelers prefer the latter playing the situation rather than the offense which is why they play much more base and also much more dime than we do.
I think the beefy 2-4 wasn't about a pressure:coverage tradeoff but rather gap assignments. It was leveraging the fact that our best two defensive lineman were able two-gappers and our nickel corner could tackle like a linebacker allowing us to account for all the gaps while also giving better coverage options with Woodson in the slot.
Of course we'll still see nickel and dime in traditional nickel and dime situations but we don't have the beefy 2-gappers to keep a hat on a hat against those balanced offensive formations anymore while in nickel. Well, we could but it would mean giving snaps to Boyd, Guion, and Pennel over Daniels, Jones, Peppers, and Neal. Despite all his nicknames on this forum Capers is pretty good at getting his best guys in the place to be successful (see Woodson, Charles and Taylor, Jason). My guess is that instead of having a 2-gapping 3-4, a 2-gapping 2-4, and a 1-gapping 2-4 we'll have a 2-gapping 3-4, a 1-gapping 3-4, and a 1-gapping 2-4. Our OLB might not be the best coverage guys but at least their diversity should make zone blitzing and disguises easier than before. A safety shell you can trust would certainly go a long way.