Terrible trade for the Bruins in hindsight
-however-
In 10 years with the Stars, he's had one deep run in the playoffs and his only Cup came as a 'yute with the Bruins. So.... does this guy really match what you're looking for in your team mantra for dynasty building? I don't know.
I mean, the Stars had not also compiled a treasure trove of young talents like the Rangers have. The Rangers are very well off at wing, goalie, and defense for a long, long time. They have all the pieces together basically at those positions. Their achilles heel is center, which can otherwise derail them without getting some young guys.
The Stars were in a different position. I'm not claiming that "snagging a young low end 1C" (as Seguin is no Crosby or McDavid, certainly) guarantees a ten year window of competition.
I'm saying the Rangers are close to it with their young talent but they lack probably 2 centers - also, maybe one more wing and one more high end defenseman - but that once they get those things they are golden.
Yes, if the Rangers could get one Seguin for Nils, Krav, and a first, and maybe another small add like Gauthier or something, I would feel tremendous. I would still be looking for a young middle six center but that's definitely not as hard to find as a young top 6 center. The Rangers won't need a McDavid, they are going to be wing-driven. They need like a Backstrom and Kuznetzov pairing.
If they trade Nils, Krav and a first for someone who walks in 6 or 18 months and they don't win a Cup (which they won't), they can't go also trading Othmann, Jones, Robertson and a first next year for a center. They need those pieces.
They'll be tapped out.
Nils and Krav have to go for core components, young and long term.