There's a chance of injury risk with anyone.
I'd say it depends on the offers you get right now. Even if LBJ leaves, I think there is a value for the younger players having some vets from whom to learn and to help it not be a complete shitshow. So if the offers are underwhelming, you keep him and see if his value goes up when he is the No. 1 option. If it doesn't...well, the offers were underwhelming anyway, so you haven't lost as much.
If Lebron leaves there will be big demand for Love, Hill, Korver at the deadline. We could load of on younger players or picks.
Plus we get rid of those players then we are pretty sure to make the lottery and keep the pick we traded to Atlanta