For the sake of convenience, it would be great to have a full-screen lock option, since it doesn't make sense to switch views while in full-screen mode. Additionally, it would be helpful if the application utilized the mod key (such as virtual machines) for better user experience.
This is a great idea - expanding this to include choosing which screen the lock goes on and more lock configuration like you said earlier is also good.
tho this feature is unrelated to lock but more related to panel properties,
Like : LockViewWhenFullscreen = True|False