I find a few house rules about knowledge's useful

To know anything about any monster from a knowledge check someone must have survived and been able to write it down or talk about it and have that knowledge get to you. New monster is an unknown factor in the world and thus there is know way that any character in the world knows anything about it. The knowledge check covers how much of the knowledge available to be learned in the books and stories of your home region (and the regions traveled through adventuring) that you have personally absorbed and have at you fingertips. And nobody can know knowledge that has yet to be discovered. This is logic of how a world works trumping RAW.
And for local knowledge-give it a home region advantage only. Possibly transferable after months or years of living someplace.
And unless the spell specifically states that it can give a command word then it doesn't. . . good grief.