I am unable to go through all your points today but I've been studying and reading up on this topic for a few weeks when I started running my raw DNA data (had it sequenced recently) through algorithms in order to analyse my genetics. The first algorithm I tried was through "Promethease", which upon first opening my html-file gave me the detected genes ordered of their magnitude. The label shown for number 3 was "lack of empathy?". Which took me back to when I was 13 when I first talked to a close friend about my suspicion of being some sort of sociopath(i am not but probably could have become one).
Now, my parents are very empathetic people. My mother, an extreme leftie, never ended up changing anything inside my mind on any such topics. I have not been altered even though I went to extremely left wing schools that literally fed us all kinds of guilt and propaganda. It never came through.
So all I wanted to leave here for now is that it really is not necessarily all environment, because I grew up with the extremes and did not discover any other opinions until I got older - which changed my entire world in a very significant way.
I will get back to this post, don't know when though. Awesome you posted this.