Tarasenko is a shooter first and foremost, and he hasn't been carrying the puck up ice (Mika or Kreider does on that line). They have to learn to read off each other, so I'm not concerned. I'd rather see those two use him more as an option TBH. Will make more space for all 3 of them. Tarasenko's bread and butter play with those 2 will be Zibanejad cycling to the the middle of the ice, Kreider in front of the net, Tarasenko on the RW half wall. Zib cycles, drops to Tarasenko, and continues to the middle of the ice taking the D with him. Tarasenko beats his man one on one, cuts to the middle from the RW half wall and follows Mika who has taken his man with him away from the circle, then Tarasenko rips it with Kreider screening.
He scored a ton of goals in St. Louis this way, but these 3 have not learned to read off each other to get the timing right yet. Their play in the offensive zone is still too positional/predictable and there's a lack of movement both with and without the puck as current. With time, I think they'll figure it out. It's a "developing chemistry" issue, not a "the player we traded for is in decline" issue.