I disagree. The game is easy enough above level 12 and making it even easier isn't the best idea. Myself, I opened the portal not before level 20 and I was already hugely overpowered without any help from books or stuff...
Yeah, but it is easy mostly because AI is completely stupid. That couple of points from books doesn't really make any difference for good player, who already is annihilating all enemies with ease. You would be just annihilating them a little faster. And no one is forcing you to use these books, if you want more challenge. But it can make a difference for some of the casual RPG players, who are constantly crying on forum because game is too hard for them. Also books are nice if you trying to play with only one character. Without many additional points to put in willpower/bodybuilding etc. it probably would be impossible to finish game solo, due to CC effects.
Well, that's a sorry excuse. Nobody forces you to level up as well. Nobody forces you to use tactics in combat.
You can always make it incredibly difficult for yourself if you want so with discipline. But that doesn't mean that the base game should be incredibly easy, should it?

I also disagree about the stupid AI. AI is ok (at least most times). Enemies are just too weak. What shall they do if my characters are almost all immune to elemental damage and if I can freeze/stund/knock down them with ease? Even the best AI wouldn't solve or improve that if the player characters are just OP...