Some people on this forum confuse nearly everyone with their stupid functional analysis. The reason for this disaster is the influence of socionics.us which is a completely miguiding website about socionics. You should trust your own intuition and type yourself by descriptions. Model A is just a model.
Judging people have a rational base function, perceiving people have an irrational base function. That's the socionics definition.
You certainly noticed that the J/P dichotomy doesn't appear in the 3-letter-names. In MBTI types are defined by dichotomies whereas they are defined by their order of functions in socionics.
Perceiving people are often more spontaneous, more tolerant, less reliable. But there are INTps who are not really spontaneous, not really tolerant and quite reliable. That's why you shouldn't type anyone only by dichotomies.
Yes, because you are Ni-INTj in socionics. If you were Ti-INTj you might think of yourself as INTP in MBTI. The best MBTI descriptions can be found on personalitypage.com.
Libertarianism? Not really. It rather matches up with Anarchism. Maybe you will be interested in religion or politics in 10 or 20 years so it is not an important aspect for typing.
btw: are you sure your Enneagram type isn't 5w4? That confuses me a bit...