Suitable build for All Ears bandit sequence?

Hi all,

So I finally got No Stone Unturned (easily over 50 vaal areas), and I'm turning my attention to All Ears. The wiki page is very helpful, but I have a couple of questions about the bandits:

1. How exactly do you use the Book of Reform to get the last two dialogs with Eramir and Greust? You buy the book, right-click it to use it, and then talk to them? Does it matter which difficulty?

2. Does it matter which difficulty you help each bandit? The wiki says help Alira in Normal, Oak in Cruel and Kraityn in Merciless, but can you swap those around?

3. Anyone want to suggest a class and build that works best with that (or another) sequence of bandit rewards? I'd like to end up with an optimised character without buying more than one book of regret ...

Thanks in advance for any thoughts,

CC