They have a future here if they cannot be sold for a product that is better/more urgently required. It is that simple. We are not the leafs and we are not the bruins; Lindy's system is not a heavy hitting one, this doesn't matter - if they play his system and hit that is fine, if they just want to hit and slow the game down then we have no need for them in this team. However, based on what i have seen of their game, they will fit in fine.
Hell, the Bruins should not even be the champs. There was a reason Vancouver burnt the night they lost and it was because of their overpayed goalie. Detroit, Chicago, Pittsburgh and Vancouver play a skilled system based around the centre position. I would rather emulate them than the Bruins. And yes, Vancouver traded for Kassian despite this, however, when you have a glut of centre you can afford and need to trade for the final piece - which they HOPE is Kassian.
Everyone would be happier if we traded Stafford for Hodgson. Why is this relevant? I would have been even happier if had traded Kotalik for Hodgson! They wanted Kassian, they got Kassian, they gave up a lot to get him.