Re: Aiki Ken and Ken justu
I have seen aikiken demonstrated with metal blades. (Iaito in this case, not shinken.) All the forms "work."
I wouldn't recommend doing this unless you have a fair amount of experience with blades, though. First, you'll bash the heck out of the blades and make their owner very unhappy unless you know what you're doing. And second, if you use live blades without a great deal of care, you're very likely to hurt someone.
If you want to study the use of blades, study a sword art.