A few things:
1 - Kakko getting signed this quickly before the draft makes me think there's still a very legit chance he's dealt. That is a very attractive price tag for us or another team. Insurance that even if nothing more than a 3rd liner, he's still only 2/3rds of a Goodrow AAV.
2 - At this point in Kakko's lack of development offensively can be chalked up to three things.
a - His foot speed and inability to gain separation is such a limit on his ceiling that currently, he's just a very skilled defensive forward.
b - When the team committed to Zibanejad and put Laf with Tro/Bread, it meant the end of Kakko. The top two lines officially became incompatible for Kakko to fit. Both scoring lines rely on the rush.
c - In the bottom six, and with Chytil's concussion and absence all season, Kakko has mostly played with minimally skilled linemates. Had Chytil remained healthy all year, a line with Kakko/Cuylle/Chytil could have been really interesting as it could have could have been a better fit for Kakko. I'm concerned that Chytil's playing style going forward may be less engaged in the corners and remaining stationary. If Chytil's game ends up becoming more like Zib at 5v5, Kakko's place on the team is even harder to understand.
In an ideal world, the Rangers would focus on transforming one of their top lines into one that can be relied up on 5v5 and in tight, playoff-style games. And to me, if that's the case, there's a place for Kakko. To me, Kakko could very well flourish on a line that has a stout strong in the corners center like Sam Bennett or a Younger Jeff Carter or Kopitar. These guys who play possession style like Kakko and bully their way to the net and have legit skill. This is why I'm ultimately afraid to move the kid because if he finds a team/line like that I could see him taking off and being an absolute pain to deal with for opponents. Sadly, despite being a #2 overall pick, we've never tried to build anything at all around Kakko (and really same thing with Laf).