If the Kings won't offer QB and no other team offers an elite blue chip prospect or Buffalo doesn't want to trade him to the East this could actually work. At first I thought Buff might not want Kempe if they blow it up since he is a bit older, but they are still going to have to ice a team next season, and if Kempe gets PP time and produces they could flip him at the deadline.
The Kings end up losing a pick this year that would probably produce their #1 d prospect if they kept it, they lose Turcotte but with C being the only area of organizational strength its managable, Kempe is what he is. I think the only way this trade could really be a big loss is if Buffalo hit big with either this years pick, or more than likely next years pick. But I have a hard time seeing a Kings team with Eichel and Kopitar down the middle being bad enough where that pick is in the top half of the first.
Some teams really struggle to find elite C's, the Kings would have two of them on the NHL roster and another player knocking on the door with elite potential in QB.