Lest I remind you that the Jets ran Morrow as the defenseman to play with Buff, in the 1st round of the playoffs, Chiarot with Myers. Enstrom stepped in for Nashville, and was hardly a game breaker. And was a heart breaker in series 3.
Thing about Chiarot-Buff is that they don't give up much space, they play relatively close in open ice, so that they force pucks to the outside. On the boards both will wreck you. So while I do think you need a contingency plan, for injuries, I don't necessarily believe that a top defenseman is a need, as long as Kulikov-Myers defend well and creating offensive zone time. I'd have no problem with Edler pushing Chiarot to #7 for depth. Morrow/Poolman as 8/9. And then the rest are preparing for next year.