My take on Keon is, he can't dribble, and god forbid he leads a break. A guy who needs to be a ball handler who cannot do those things is very limited, regardless of how good he is defensively and catch and shoot. He deserved more minutes than he got, but probably not a ton more.
This has nothing to do with the value of the trade, this is just him in a box. I think there is a way to gameplay for him to succeed, but you need to have strong personnel around him. I think he will flourish in Cleveland.