I think Karlsson is unreal, the best offensive dman in a long time. He's a game changer, and so much fun to watch. Add in Mark Stone, who is one of the top offensive wingers in the NHL, and that's a huge package. But, any Sens fan saying NO to this deal is not seeing the big picture. McDavid has more value than any player to ever enter the league. The combination of talent/skill and hype/interest in this kid is unparalleled. The value he brings to any team has never been heard of before. Maybe he won't live up to the hype, and have the success that many are predicting for him at this point, that's a very real possibility, but right now, he has delivered, and the hype train is still on track and running smoothly.
I get that trading one of the best offensive D and top 10 winger would be a huge blow to any team when it comes to their chances of competing on the ice. But what McDavid adds, at least in the next couple years is much bigger than that. Before McDavid showed up, no one cared about the Oilers, but once he arrived, they are in the news all over the place. He's a special kid.