I'd try it for a good portion of the season.
Nylander can drive his own line, I want him on the third line regardless so we can have 3 scoring lines.
Hopefully, this doesn't mean moving Tavares to the wing.
Domi - Matthews - Marner
Robertson - Tavares - Bertuzzi
Knies - Nylander - Jarnkrok
Lafferty - Kampf - Reaves
Would be by far the best C depth in the league, and we become a matchup nightmare.
If Nylander can transition well, that is 3x 1C and a 3C as our C depth.
Before anyone complains about someone playing 3rd line who should be getting extra minutes, Keefe moves guys up and down the lineup based on faceoffs so everyone will get their ice time. Toss Nylander on the wing of Tavares if there is an ozone draw instead of Robertson (or however the lines are).
I really wish we never signed Reaves so Holmberg and Robertson could get a good look, I think Holmberg is super underrated, 30 points on the 4th line while being responsible in all zones is good.