What struck me as right about me for NT was doing something because it made sense; if it doesn't make sense, I don't do it. I do follow tradition. If I see a use for it. I follow the rules. If I see a use for them. I refuse to blindly follow authority because it's there; if it holds up, it is worth following (although I will make every effort to retain my independence and freedom of thought; autonomy is important to me).
That
could be ESTJ.
But look at what you're doing. you don't follow tradition, really. You blatantly just said you don't follow authority just because it's there; you only follow what makes sense!

Throwing out tradition if it doesn't make sense is
not following tradition!
ESTJ actually does have the sort of attitude you describe. Basically, you learn what works and what doesn't work. You also want structure and organization, to make a process sensible and efficient. Many times the organization has already developed a process that is workable.
But Te is the predominate factor, *not* Si. Si is a reference point (hence sticking with "what already is" or "what already has worked") but if Te can be convinced a change is necessary, ESTJ will quickly implement the change and then enforce it as the new standard.
Still, xNTJ also has Te as dominant/secondary, so you need to consider those.
(As an aside, now that I am thinking about it, male ISTJs are funny -- probably the most wavering/indecisive of the male STs. Basically, I think their need for specific full detail before making decisions is coupled with not wanting to be responsible for making the wrong choice, so they usually hem and haw unless they are in an area of competence, where all the data can be quantified. )
However, certain aspects of the NT simply didn't fit. One of these was their extreme bedraggledness and disconcern for aesthetics. I always attempt to dress well. I shit all over fashion, but I still believe in a tidy appearance, because first impressions count; there is no use denying this. To get the job, you have to look good. To get in with a crowd in order to gain more power, you're gonna have to look flash.
Just because there is more tendency for NT to look shoddy or be unconcerned about fashion doesn't mean that individual NTs cannot be concerned about their appearance or about fashion. Not all NT's look shoddy.
Male INTPs are probably the worst, to be honest... because they generally don't care nor see value most the time in developing an eye for clothes. But it doesn't mean they can't develop it, especially if they find an important reason to do so. They just don't gravitate towards it.
xNTJ will probably be your best dressers in the "professional" sense, since they often have motivation enough to want to look respectable (to get what they want in life), look competent, provide proper challenge to their peers at work, etc. INTJ women are very well put-together, usually. Note that your combo here is Te/Ni/Se/Fi -- so the Te uses clothes logically, to accomplish their purposes (and won't let them undermine how competently they're perceived by others), Se has the tactile/visual sensation qualities, and Fi expresses personal values/tastes.
Most aesthetic probably would be ENTP, which likes to dabble in everything external... clothes being one of those things. Coupled with their general amorousness and need to move through social circles, they might very well develop something with flash, that is attractive to others.
Another characterstic of the NT which simply didn't fit me was that they never seem to have any inner convictions. They can never say "I just know this". Note that I will never ever use this when I'm studying philosophy, because a broad, open and doubting mind is a prerequisite for studying it. However, in real life, for practicality's sake, dogmatism and conviction are needed; confidence in your views even if they're not well backed up is necessary; it's a requirement. One must be able to say "I am right" and believe it.
If you were naturally an ST type, would you even need to think through this? And would you approach it the same way? Wouldn't you start with, "I can't make any decisions unless I'm sure about what I'm doing... yet I've learned I had to have a broad,open, doubting mind" etc.? See the order you approached things in? You started with NT, then logicked your way to ST... NOT the inverse.
Lots of NTs also do not remain abstract, especially the NTJ. They learn early or late that, to actually accomplish anything and further their own learning/competence, they'll need to make decisions. NTPs will agonize over it, but NTJs are very prone to make the decisions as a matter of course. (My INTJ drives me nutty, he's constantly making decisions or pushing for decisions, sometimes when it doesn't even make sense, when he gets anxious about deadlines and project goals.)
Another thing is this self-doubt which seems to occupy the NT's mind. I do not self-doubt. I might self-doubt once or twice a year when there is clear evidence that I am failing at something. However, self-doubt for the NT appears to be a big part of their mindset.
Again, talk to some NTJ types. NTPs are riddled with self-doubt. NTJs will LOOK at least on the surface to be very confident and sure of themselves.
Perhaps those wiser than I in MBTI lore can help me decipher where I'm making mistakes or misunderstanding the true core of a given type.
No, I think you've managed to befuddle both yourself AND the rest of us.
You know what I get most of all when I see all these posts?
You think too much, that's what. How many threads have you created on this topic so far?
You think so long and hard you confuse the issue because you're not determining any "key data" and instead prioritizing all of it.
Figuring out your type is going to be easier than you probably have made it. (although yes, there are some who just are hard to type, in general.) I'd just keep an eye on myself as I went throughout my day and see what function I automatically use. Then I'd see what internal function I use to support it. Don't THINK about it all, just observe yourself through a detached third-party view... your behavior as well as the pattern of your thoughts.
See if that reflects at all upon what matters to you.