The human predicate is necessary for CEV if I remember correctly, you would want to extrapolate the volition of everyone currently informationally smeared across the planet as well as the more concentrated humans.

I think the (non)person predicate is necessary for CEV only to avoid stomping on persons while running it. It may not be essential to try to make the initial dynamic as expansive as possible, since a less-expansive one can always output "learn enough to do a broader CEV, and do so superseding this".