Upside wise, I think he can be a 2C in the NHL. Like was already touched on, the skill is there and he has shown flashes of what he can do.
But its a matter of whether he can do that consistently and well enough to actually stick at that kind of upside. The good news is his all around game, his effort level, his instincts, everything else looks good so that even if the offensive puck skills dont translate, I think you still have an NHL forward here. Its basically just a question of whether you've got a 2C who can chip in ~20 Goals and 30-40 assists, or if he's more of a 3C who can pot 15 Goals and 15 Assists but never enough offensively to be relied upon in a Top 6 role.
Personally, I think he's going to wind up a 3C, and a damn good one at that. And if the organization works with him I think he could be a fantastic 3rd wheel for us behind Mack and Kadri.
I actually think he's forced Bednar to play him a little more this preseason and is earning himself a real look at a possible NHL roster spot on opening night, depending on how a couple injuries/Rantanen situation plays out.
Right now I think we've got:
Mack/Gabe/Kadri/Burakovsky/Donskoi/Compher/Jost/Nieto/Calvert
Those 9 guys are(barring injuries) going to play opening night. Then you've got Bellemare, and Wilson who are dealing with injuries right now and might not be available opening night, and you have the Rantanen situation that may make him unavailable.
So right now maybe 3 spots in the opening lineup up for grabs. And IMO you've got Nichushkin, Kamenev, Greer, Kaut, Bowers, and LOC who have either played well enough to make a case to be involved(This applies to Kaut, Bowers, and LOC), or they're still part of the equation simply because of age/opportunity.
What I think ends up happening if we have 3 spots available opening night, is Nuke, Kamenev, and LOC get the spots with Greer the 13th forward. Who I beleive have been most deserving of the 3 spots would be LOC, Nuke, and Bowers with Kaut the 13th forward.