The problem with the term "Tavares money" is that Tavares makes 3m less per year on average than he should.
If we were closer to contending, I'd trade for Kessel. I don't put a single bit of stock in the whole "he disappears" and "bad attitude" and all that. He's a superstar winger with the whole-package offensive skillset, whose been playing on a terrible team with a terrible culture with almost entirely terrible forwards up until JVR joined the team.
But right now, we're likely to see Kessel begin to decline, and it's not worth trading the 6th overall this year when the best value from trading for Kessel would come in the first year or two after the deal, and not years 3, 4, or 5.
As for JVR, I just don't see him as the gamebreaker that Kessel is. But it's gonna be really interesting seeing how that team performs under competent management. JVR and Kessel could both easily have another guy if they end up spending next season with a center more fitting a top-6 role.