Now I remember who he reminds me of:
Note - this is not meant to be a critique, merely a comparison of their skillsets & athleticism. Carlsson pretty clearly has the better awareness and processing, and is definitely more of a playmaker, but Kotkaniemi was extremely impressive during his draft year - watch those highlights. Both guys had great hands (Carlsson's are better better) with similar posture and agility "issues".
Obviously I think he'll be better than Kotkaniemi, but there are some pretty striking similarities.