Tavares isn't going anywhere. Tough to find someone that can take on $11M. He's still solid, but is clearly on the decline. Plus I don't see him waiving his NMC.
Matthews is going nowhere.
Marner is probably not going anywhere. Again, almost $11M...hard to find a taker without taking on comparable money. Tremendous talent...is great with Matthews...and do you see any deal where the Leafs come out better after moving him?
Nylander is the obvious guy. 30+ goal scorer. 80 point guy. $7M ticket...very team friendly. Personally, I don't think I'd move him, BUT, I would float his name out there and see if there are any GM's that have a big hardon for him...maybe someone is willing to pay a hefty price that makes sense for the Leafs.
I'd rather look at doing something with Kerfoot/Muzzin/Holl. I like the core...it's that second tier of supporting characters that needs work.
All that said, need a goalie that is a legit game changer. They don't grow on trees, but they have to find one...somewhere, somehow.