I wouldn't mind a black Superman but not Clark Kent, just a whole different take.
A retro black Superman showing up in 1938 could really be interesting. But standard Superman as retro? As much as I personally would love a retro Golden Age take, I also cannot see the PTB doing that for any reason but thinking Superman is an outdated concept. Besides, Superman running around kidnapping crooked politicians and war profiteers? The same "Not muh Superman" and "Man of Murder" crowd that panned MoS would declare the original Superman not Superman.
I certainly would not rehash his origin again, just imply it's more or less the standard origin.
I also liked Cavill. But I cannot see using him yet making it clear it's a different take.