>It seems there is a change in the book loottable
Yes, some books are replaced with map fragments, but it's around 1/10 in the early areas, so it shouldn't change much. The rest is just randomness (or the areas you choose to explore, since the selection varies between areas).
>I encountered Raemus heir.
Yes, you got scammed. He's a reminder not to trust random strangers (and you could avoid this result).
But you aren't the first one to get angry at him, so maybe I'll add some way to get back at him. Not assassins, though.