What gives him the best chance to be such a player? Playing on a line centered by ZBad or one by Chytil or Howden? Or do you believe his production will be the same no matter what? Or was he not brought here to maximize production?
As for "who cares", frankly anyone that was pounding the table that by signing such a player it relieves pressure from playing in a role that they are not ready for. Or does merely playing on a line with Panarin mean that you are ready for any such role?
The scenario where a team has to be concerned about Panarin's line and another line coming onto the ice and scoring. A choice would have to be made. Some teams don't have two pairings they would want to go out there against lines like that. We should know this because for the last 10 years before rebuilding, the Rangers made it their thing with depth scoring that would allow them to win games over other teams. Spread the talent around and you'll take advantage of weak 2nd pairs on bad teams and not as good 3rd pairs on good teams.
Panarin's production will not really drop off at all based on his center. He's played with younger, older, more defensive, more offensive types and he consistently hits his totals, year after year.
If line placement is a big deal, guess the Hawks weren't maxing out Pat Kane's abilities playing him with another undersized scoring winger and a center that couldn't crack the Coyotes. He should have been playing with Toews and Saad.
If we go out there and stack one line, as good as it may be, we'll be more like the Oilers than anything else. A one line team that if you shut them down, you're pretty much going to win.
Believe it or not, this team isn't going to intentionally tank, and splitting Panarin and Zibanejad so the team has two scoring lines would be the way to go IMO. They can be stacked together late in games and when we really need a goal, but having all the power on one line and leaving 2-4 with all our young players and/or bottom 6ers spread out will not end up well for the team and their development.
Case in point, look at how Buchnevich picked it up playing with Kreider and Zibanejad. Now that he is coming into his own, there is a much better chance now that he can go out there and help be a bigger part of his own line. This season, that has the chance to be the 3rd line, especially with the talent coming in on RW. Kakko and Kravtsov's skill level could make them great complimentary players for Zibanejad and Panarin. Over time, they get adjusted to the league and they don't have to be on those lines. They could drive play themselves.