Welcome to the forums Epsilon, I'm new around here too.
You talked about spending long hours thinking about the book and improving your character. It also sounds like you also haven't finished the book (my fourth character has only finished Act I, the other three characters I gave up on).
My first character tried to max out armour, but I found combat was boring when I didn't have enough speed, I found I was rolling the dice a lot, getting hit a lot for a small amount of damage, and then eventually dying.
By my fourth character I felt like I was starting to get a good balance of stats and abilities, but I also found that the I had tried almost all the paths in the green and orange quests. I knew the consequences on my choices so those moment lacked surprise and was less fun. I was thinking more about min-maxing my character than the story and the choices.
I've come to the conclusion that I'll probably have more fun finishing the book if I stop re-rolling and just stick with my current character all the way through to the end of the book.
So... how far have you got through the book? What have your experiences with it being like?