Small catch on the (any Actor)? of nextElement(isolatedTo:) -- this should be (any AnyActor)?, because iteration inside a distributed actor should work the same way as in an actor. Or alternatively make it a generic parameter?
It's also tempting to go ahead and perhaps implement the being-pitched in [Pitch] Inheriting the caller's actor isolation #isolated or the moral equivalent of it, so we can spell the parameter as isolatedTo actor: A = #isolated (or alternative name it might get) so we don't have to invent a special way to summon the actor value but rely on the # default parameter 