I'm unsure if they should propagate to the child directly. If this happens then when you want to edit a operating system setting for a parent you'd have to do it child by child manually (or we'd have to wipe each child when u edit parent, which would make overrides hard to track). Rather when OS is blank for a child I think we should pull this info from the parent or parent's parent and when set it'd override the parents setting. This'll make it easier to manage the OS setting with a few larger groups rather than child by child while still allowing flexibility to override what the parents settings are.

+1 for not saving it directly to the child host group, but fallback to the parent if not set on child