Neutrality bores me to tears, and I've never played a neutral Geralt.
Well, I'm the opposite. If I can stay neutral I will, because especially in politics I think it would not be my business.
So basically, what I am doing is I try to do what I would do if I was in the very same situation and if I was a Witcher and if I had experienced all that stuff in TW1 and TW2 up to the point I am at the moment.
Which is basically that some monsters are dangerous and have to be killed, others can be reasoned with or are not dangerous and can be spared. Humans and Elves as well as Dwarves can be as much a monster as any other creature can be and if they are they deserve punishment, either by arrest or by death.
In terms of politics I support characters which ideals I share but in major political decisions I'm keeping my hands off and stay neutral if possible.
And IF I don't stay neutral then I most probably only have my own goals in mind and try to get myself an advantage.
That's how I play it.