The baby insult aside it's a legit discussion. My first thought was neither but why not sign Nylander, unfortunately let Gardiner walk, trade Kadri and anoint Nylander the team's 3rd line center/1st unit PP guy/Matthews' late game winger?
It would super nice if there was more cap space to go around but there just isn't. Even avoiding any big mistakes, there's no way to create a super team any longer. You have to make decisions. Chicago had Kane, Toews, Seabrook, Keith and Hossa (with a now illegal cap circumvention contract) and a balance of a team that was constantly turned over. Right now I see Tavares, Matthews, Marner, Rielly and Mr.X as the Leafs' big earners. Is Mr. X Nylander or another defenseman? It seems like the template is for that player to be a defenseman. I guess the Leafs could continue to be top heavy at forward but that will leave a lot of scrambling for defensemen every summer. But the reality is that players we like will have to leave every summer for the next 6 to 10 years. To keep Nylander and all, Kadri and Gardiner would have to be the first casualties of players you'd want to keep but can't. Finding a place for Marleau's a given. But later it could be Zaitsev.
A similar team to Chicago would be Pittsburgh. Crosby, Malkin, Kessel (discounted), Letang and Fleury in their recent Cup seasons then a scramble for the balance of the lineup. Way way back they had this real nice forward piece Jordan Staal who it was impossible to keep long term. They didn't move him because they didn't value him, they moved him because there was a cap crunch looming.
But there's some good news: look at what happened long term in Chicago and Pittsburgh. At time marches on, the contracts to their superstars become smaller and smaller fractions of their total cap hits allowing them to acquire more expensive support talent. So after the pain of watching players we'd really love keep have to go, we'll eventually see better reinforcements (in theory) as time marches forward.