Just please, please don't be suckered by Gilbert "Creme" Brule! He shows up once every three years to fool GMs into thinking he belongs in the NHL. He's a classic tweener who has never proven he can produce in a third-line role and isn't consistent enough in ANY role.
He presumably would cost very little, considering he's still looking for work, and if he doesn't pan out you send him to Syracuse.
The problem is Tyler Johnson's probably your best option at center from within the system right now. I don't share the concerns about Killorn's skating, but I do think he's better suited to play wing in the pro given the north-south style he plays, and Namestnikov is still a year or two away. Mind you, Johnson's got Ferrari caliber speed, but he weighs like 5 pounds.