Marner is definitely off the table too, and Nylander is pretty close to off the table as well unless we're getting a top2 RD.
I think it's inevitable that JVR will be a Duck. I could see Leafs having interest in Vatanen. Not sure what else would be included to make it work.
No team in the history of the league would trade a top2 RD for Nylander.
In fact, the last time a "top-2" defenseman was traded AT ALL in this entire league is Chris Pronger, and that was quite a long time ago and was forced by a unique set of circumstances in which he HAD to be traded, only because two hall of fame defensemen were rostered on one team and they couldn't afford the cap. Do any teams in the league have 2x top-10 defenders in history of the game, just won a cup, and are cap strangled? No. It won't happen again either.
This set of circumstances is very rare to be repeated, thus you will not see many top pairing defenders in trades. You'll need to give up a LOT more than a offensively oriented rookie winger who won't even hit 60 points this year and he's in a tremendous situation to score points on the leafs right now.
Like people say, Hall for Larsson wasn't an anomaly. That is the premium you pay to acquire a defenseman which are a lot harder to predict/develop in the draft and therefore have much higher value when one of them truly pans out into a top pairing guy.
Hall's value at that time drastically outweighs Nylander's now, so you'd be looking at a low-end top-4 defender as a return, NOT a "young top-2 rhd with huge upside and talent"