Any negative of Cullen possibly bumping a young guy out of the team is more than mitigated by the leadership he’ll bring to the young players, namely Sprong & ZAR & Simon.
AND, specifically I think, he can really help bring along and mentor a guy like Blueger who is clearly knocking on the door. Whether they trade Brass for a LW or put Brass on LW (which I think fills a need and kind of kills 2 birds with 1 stone while still giving us versatility should we need to move Brass back to C), then Cullen could help Blueger transition into the 4th line spot if Sheahan is on the 3rd line.