I gotta say, the book slam thing sounds like it was lifted wholesale from a comedy fantasy game. Totally doesn't fit in with any of the other stuff that I have heard about this game. Just sounds... silly. Ridiculous. "Oh, well, I'm in combat, I'll just close my spell book, thus losing my place, and then bash someone in the face with it, thus destroying the spine. And of course I have to get close enough to do so, which means getting inside that sword-wielder's reach, which is something you ordinarily would want to avoid trying because it's, you know, suicidal. And anyway, it's a huge book weighing five pounds and is made mostly of paper, which makes it an AWFUL weapon (awkwardly shaped, unbalanced, hard to swing, well-padded, etc), so awful that you would be an order of magnitude better off charging someone's fist with magical energy and hitting them with that."
Here's a vote for two different ways to get a magic-using character out of engagement: one, a magically charged *fist* (or wand or staff or whatever, if you're having those... but if s/he's using a grimoire, then a fist), or two, a very short-range teleport.
