Natural sciences! Biology (animals as well as plants, a bit of more specific human biology too) and geology, that kind of things. I hope to become a teacher in natural sciences for teenagers students (secondary school? I'm not sure how the system works in Switzerland)
I liked the idea of the future with a system controlling the people by analyzing them like that, it's really interesting, especially since they put the future close enough to us to include ''old timers'' like Masaoka with a way of thinking we know, it shows the difference between what we could think and what the characters in this future think.
A thing I'd reproach them is that they focus a bit too much on Akane and Kogami while the other characters can be interesting too. And sometimes it's a bit too gore to be gore.
But it has good ideas, I should watch it a second time someday.
My favorite character is Ginoza.
And you? What did you think about it?