I can see Cindy McCain, who'd make a pretty decent Ambassador to London, if she listens to the professional staff.
Sure, Iger's done HK and Shanghai Disneylands but this seems weird since the Ambassador to Beijing is usually driven by personal relationships/China experience, and Iger doesn't seem to have either (no real links to power structures in Beijing/DC and sure Disney has expanded its China presence under his watch, but he's no China hand).
One of the few times I agree with Fox News. Bob Iger's an odd choice for ambassador to China. Not that I mind, he helps business ties between the two superpowers. But I'm sure Republicans would cry foul.