For the "nerf it" community:
if you think running through the game to reach the teller of secrets at Level 5 and then get 15 (?) books is overpowered ... don't do it!
No one is forcing you to do that, but I as a casual player would like to have a chance to get a few of these books - one at each level AFAIK.
No, I am actually forced to do it. I have major OCD and if I do not go get those books at the earliest level possible (aka, missing no books) then I will end up freaking out and throwing up in the bathroom. Reducing it down to one or two sets (so both characters can have them) is both more balanced from a game perspective and would help with my particular issue :P