I feel a strong connection to my 1 integration. Maitri's description of the soul child for a 4 is spot on for me then. Being INFP with inferior Te, e1 looks very much like my animus. And then add the 8 integration for my 5 wing, which looks like another side of Te for me. The parallels between that & my Jungian type is very interesting to me.
This perhaps is exaggerated by being sp-dom. I feel the instincts are colored by the core type, so for me sp-dom is not about physical security or health. It's a masochistic attitude towards my needs at times, where I'll take on a self-denial that leads to an indulgence elsewhere (ie. I'll sacrifice my desire for some connection with someone, perhaps feeling not good enough, and then feel justified in self-pampering that can include a sense of being above certain standards others adhere to). This is also aggravated by having a 5 wing with its "greedy hoarding" & stinginess of time, energy & emotions. On the outside, I can be good at giving the appearance of needing no one, and perhaps wanting no one.
This all makes me less dramatic than the stereotypical 4 in behavior & direct expression. I've been called cold and indifferent. But I have also been called temperamental, ornery and a pre-madonna. I can create an enviable image that makes me seem untouchable to people, sort of putting glass walls all around myself, or I'll use the comparison to art - I'll make myself into a piece to admire but only suited for viewing behind ropes because it's not "own-able". I think other 4s are better at being openly vulnerable, which may draw others but become masochistic in another way.
The sx part comes out of me in having a bitter dissatisfaction with things that looks more angry than pitifully sad. I can do pitifully sad, but I'll have such a resentment at even being put into that situation that I end up appearing more hostile. I've been told by a few people that there is something violent about me simmering just below the surface at times. I don't think most pick up on that though, because most just see the very contained 4w5 sp side, with a Fi mask of coolness to add to it.
In short - far less smooshy emotion than INFPs of the e9 variety, the appearance of being cooler & more cerebral than say, ENFP e4s, and less inclined to sacrifice the self through reaching out for too high ideals (as NFJs might) than to do a sort of gravitational collapse into yourself from self-loathing.
I don't buy into tri-type/fix. It's superfluous to me in light of how core type connects you to every type through wings & integration/disintegration points. I think it becomes a forer effect where people parade their type like some badge (ie. like their astrological sign) instead of seeing how every fixation is an unhealthy lens they are seeing reality through & that their experience of the other fixations is in relation to their core fix (ie. we all experience far, lust, laziness, etc). This just rings more to true to me as far as how I think the human psychology works. The other theory is cute, but is just too linear. It doesn't have enough of a interconnected energy between its parts, the way a body sort of works collectively to move as a whole, yet each part plays a different role in that, some exerting more influence than others in a movement. Tri-fix sounds more like a role one takes on in the face of certain contexts, aka personas, and how these form your general persona; and so I find it a detractor from really unearthing your ego.