On the subject of lean theology

It is not a specific field. In my opinion, there is no Jewish theology at all. There are some fundamental truths that are not "Jewish," since true facts are true for everyone, regardless of whether we learned them from a Jewish source or not, and false facts are false for everyone, regardless of their source. God created the world and gave the Torah and perhaps also brought us out of Egypt, that's about the entirety of the correct facts (in my opinion). Everything else is speculation by various people, which if you want, you will accept, and if you don't, then you won't.