It's a TERRIBLE idea to give up players for a first round pick. The only reason - THE ONLY REASON - anyone here wants to do it is because you want to make draft day interesting. There's no other reason.
But in reality, we are a team trying to win now. Do you really think it would be wise to give up a guy like Hagelin for a draft pick who - AT BEST! - will take 2-3 years to crack the NHL, and another few years to reach his prime? And half the players drafted in the first round outside of the top-10 NEVER make the NHL.
But even if the player does make it, how does it make sense to give up a player right now to get someone who'll only be useful in 4-6 years? Aren't we trying to win now while Lundqvist is still playing and Nash is in his prime?