Maccelli's one of those players who needs good linemates to be good. Borderline elite passing and vision, but if he's not playing with talented offensive players neither of those skills translate.
Utah's wingers are good now. In the top 6 you have Keller, Schmaltz, Guenther... and Jack McBain's been playing with Cooley / Guenther to provide physicality, which is definitely working as both Cooley and Guenther are just under a point a game and are looking good doing it.
Anyway Maccelli hasn't really been in the top six, he's mostly been playing with Crouse and Bjustad this year, Crouse in particular has been inexplicably bad. In the future you have Iginla and But coming so imo very little chance he'll regain top six minutes if he stays with the team.
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Hopefully he gets traded somewhere, he's a good player and can definitely contribute in the proper situation. Maybe a place like Chicago if they're willing to give up a 3rd or ideally a 2nd for him (he's 24 years old). He needs that right situation though.
EDIT: Chicago wouldn't give up a 2nd for him, they'll pick so early their 2nd is basically equivalent to a late 1st. To me, their 3rd seems like fair value