Taking a flier on Granlund, assuming no one else wants to, is not even remotely a bad idea. Tarasenko will be out and you have to add another body who can at least manage some sort of point production within the first two lines. If we trade Bozak at the supposed deadline, then at least you have someone who is able to take faceoffs when need be. He is a decent forward acquisition for literally zero assets, can score 50 points, and would fill a need of the time being.
To me, his role in Nashville was undefined and he flipped linemates pretty regularly (Turris to Duchene to Bonino), but I view our center depth much more highly than Nashville's. I mean last year Johansen was their leading scorer, and he only hit 64 points; Josi was the second leading scorer. This year, Josi was their leading scorer at 65 pts in 69 games, Forsberg being behind him with 48 pts in 63 games. Compare that with the Blues where they had ROR, Perron, Schwartz, and Schenn all hit above 50 pts (all of them either hit 60 or were quite close) in 71 games AND they were without Tarasenko for the majority of the year. So yes, I would say the Blues are more offense oriented than Nashville, which is apparent given that Nashville's top scorer has been a defenseman for the past 2 years.
There's nothing bad with saying that about the Blues. They proved they could win a cup with the recipe they have going. But you're not going to replace top tier defense lost in Petro with a guy like Granlund, let alone a forward, so I don't think it's necessary to put it in that light.