Okay, that is fine, but it just means we need someone to design Normal and Hard difficulties. (And just so you know, it isn't that easy, I've never been able to beat a Keen game without cheating as far as I can remember.)
How would you be implementing these? Alternative level files, or hard coding? Because hard coding would be inflexible, but alt. level files might have legality issues with Keen 2 and 3... Or are you doing something else? I'm a little curious.