Sams contract is a bad contract in my opinion, or he'd probably have more trade value around the league.
There are a LOT worse contracts in the league than Sam's. If we wanted to move him, I don't think we'd have a problem.
And, as I said, we're not riddled with bad contracts. No team has 100% great contracts.
I'm not sure what the rest of your post has to do with King. We're in this position primarily because of acquiring Brand. And I don't think we're in a bad position. Our tradable chips have simply progressed to where they're almost untradable, and that's a good thing.
Most of the players who have had their value reduced to contract are primarily of Stefanski's doing. Iguodala and Williams, after their BYC period is up of course, would have substantially greater trade value if they weren't signed to the deal they are, although I think Williams will eventually gain back his trade value I think.
If you're only willing to trade 4 assets on the team, 2 of which are bench players, most teams aren't going to have many trade assets.