Chabot
Gustafsson
Ellis
Sergachev
Dunn
Niskanen
Chabot is the only clearcut answer here.
Gustafsson could regress, his previous numbers don't really suggest this season is repeatable - it's likely a career year for him. Though, if he maintains 1 LD duties, there's little reason to believe he isn't good for 40+ next year. I just don't think he's a 60 pt guy.
Ellis is a reliable guy, good for ~40 points. Handicapped by the depth ahead of him in Nashville.
Both Dunn and Sergachev are buried down the lineup (PP time, linemates) but show promise to grow on the 35 pts they just put up this year.
Niskanen is the only wrong answer I see. He's a clear step back on everyone else you listed.