Quoting: EnvironmentalTwister
I'd do it. I'd only sign one of Fast/Simmonds to give them a bit more cap space, and have a cheaper forward extra.
Without Marner, keeping Johnsson/Kerfoot is important.
And you get 2 mid 1st rounders to have cheap ELC talent to replace the bottom 6 in the long run.
My thought here is that, sure, in a bubble, you lose the Marner trade. But if that new found cap space lets you sign Pietrangelo, then you're essentially moving Marner for Pietrangelo + Severson + 2 mid-1sts, which obviously looks a hell of a lot nicer. I'm only making that move if it's certain that Petro's coming home.
I think that losing Marner at forward is a pretty big loss obviously, but the insane improvement on defence is more than worth it. And this team was pretty much #1 in goals for, so sacrificing some of that to assemble the best D corps in the league is so WORTH it. You still have a one-two punch of Matthews and Tavares to drive your top 2 lines. Then you've also got an incredible 30+ goal, 70+ point talent in William Nylander. Add in complementary pieces like Andreas Johnsson, Zach Hyman, Nick Robertson, and your top 6 is fantastic.
The depth of the forwards arguably improves here as well, as you're essentially swapping Kapanen and Gauthier for Jesper Fast and Wayne Simmonds. ~40 points from Kapanen,~15 from Gauthier for ~35 from Fast and ~30 from Simmonds, along with the experience they bring and the great physicality that Simmonds would offer you.