It's way too early to throw Blashill under the bus. He doesn't have much to work with.
I agree that's its too early to torch Blash. But I'm not convinced that he hasn't got much to work with. Tatar and Nyquist have both proven they're capable goal scorers. Mrazek is a stud. Larkin is a budding star. Dats and Z are aging, but still reasonably productive. Kronwall and Green are higher end puck movers and Dekeyser is a first rate two way defenseman. Abby is also a reasonably productive complimentary piece.
Its also not unreasonable to have expected Richards, Pulkkinen, Sheahan, and Smith to be quality depth pieces.
These guys aren't mediocre players. Its troubling that, with the exception of Larkin, every single one of them is having a worse season than they did one year ago. The fact that the lack of production is so universal, suggests to me that its a coaching issue. Part of it is the anemic power play. If that's even reasonably good all these guys point totals start looking more like we are accustomed to. But if its not the coaching then I don't know how else to explain a near team wide downward slide between one year and the next.