It's gonna be a long couple of years.
If you trade Doughty, you have to trade everyone north of age 27, because it all falls apart without him. I know he's not the most popular player on this forum, but without him, this team is in the gutter. Kopitar is magic, but Doughty is the linchpin, two completely different Kings teams played this year, the one with Drew on the ice, and the one without.
I don't think him moving on to TO is that far fetched, but even as a given, you're gonna have to give up assets you don't want to. As for suggesting that will hurt TOs future, well, getting a top-3 defenseman in the game to shore up your top pairing and slot everyone correctly is easily more valuable than Willie Nylander.