Mfw people say Stirner wasn't a leftist

Oh yes, he obviously thinks that states have no legitimate authority, but I'm just pointing out that not all statists have the state as their ultimate God and master.

If every single individual exclusively cares about their self interest and completely ignores any form of norm, in terms of social roles, morality, and even basic humanity, then how can a society composed of such individuals even work or accomplish anything?

Wouldn't it be like having multiple hands handling one giant dough to make a pizza?
Some would use too much flour on one side, others would use none, some would prepare it to be bread with sesame instead, the end result would be a disjointed badly cooked monstrosity.

He outlines this roughly in terms of a union of egoists. Basically, people just have to come together, talk with one another and compromise about what they want if their self-interests contradict

It's called anyone who is a good capitalist.

Rather utopian.
When presenting an utopian setting, pretty much any ideology could work within it's convenient boundaries.
That kind of scenario and subsequent mental masturbation is of little value to the common man and his daily struggles.

Well, extreme cases, anarco capitalists i suppose.
The average capitalist can coexist with the state.
Or be "regulated" and "contained" by the state, if you want a more honest description, i guess.

One man can only do so much. Cooperation is generally in the individual's self-interest.

I feel a slippery slope.
This seems to be a transitional philosophy rather than a stable, long term structure.

Keep in mind that egoism is a set of personal ethics combined with a critique of ideology. A union of egoists isn't something an egoist would probably work for, but is something that would have to occur when egoists encounter each other and don't want to destroy each other.

Stability is for fags anyway, though.

Absolute self interest is your own suffering, never mind that of others.

My absolute self interest is absolute happiness and absence of suffering for myself, and all the people significant to me.
I want people to be happy because that makes me happy and being happy is my #1 priority.
My goal is not to make people happy, as plenty of things i can do make me happy, but anything that makes other people unhappy will make me unhappy, and thus goes against my self interest.

Even when it's people that i hate and i feel are harmful to others, i don't really have any interest or gain any schadenfreude in seeing them suffer.
Ideally, i'd like them to be removed from society, or if they're especially harmful, to be executed and thus removed from everyone's lives permanently, ensuring also the removal of a source of suffering for those that they've been harming.

Stirner doesn't advocate for self-interest, he advocates ownness, the control you have over yourself as your own property, with your ego, your creative nothing, being able to create and dissolve in itself, free of spooks. One such spook is hedonism which he decried (if you ever read TEAIO you'll know this); this is what Ayn Rand fundamentally missed the point of, she started with "work for your own self-interest" and then went on to define what your self-interest should be, material gain. Hedonism puts the sensual self above your own ego, sacrificing yourself to a fixed idea of pleasure completely uncontrollable over yourself and letting desire rule your own ego.

If THIS is true, then the entire thread aside this post i've talked to doesn't get it.
And i go back to my original post of the "next step":

But only if -this- interpretation is what it's actually all about.
Because in this case the next logical step becomes cynism, and the point Diogenes tried to make his entire life.

But you have attachment to your "self", which causes suffering in the long run - due to ageing and illness and eventually death that will inevitably affect you.
You also get hurt when people will attack you or the things you identify with (by virtue of making this identity part of what you call your 'self').

You have good intentions (aside maybe from the killing aspect) but attachment to self only causes yourself to suffer. Detachment from self dosen't mean you need to be a walking mat for everyone, it just means that you can be free of the race to outrun death.

While I believe it is possible to live in mutual self interest with those around oneself, I do not think it is a good strateg for eliminating suffering, either of the practitioner of the ideology or others within the system. But in any anarchist society there is freedom of association anyway. You don't need to be attached to the (ironically spooky) self.

This is a delusion. You don't control yourself, you don't have control over your form, mental processes, or even your position in the world. At best you can try to affect these things, but ultimately you don't have control over that. And if you don't recognise that, life will be wrought with feelings of inadequacy and helplessness.

No, you can't do that. You can imagine that you're free from spooks, but the greatest delusion of them all is caring so much for this body until it dies, absorbed in trying to keep it safe from harm and control it.

I contend that even the most basic of egoist actions involve uncontrollable desire; the desire to stop the ego from deteriorating and to keep it persisting (which, being mortal, cannot be stopped). I don't think there is any merit in the distinction between the "sensual self" and the "ego", as ultimately it is the same thing experiencing the sense pleasures.

You can't stop putting the sense pleasures above your own ego so long as you think that there is some kind of substance to the pleasures (of the five traditional senses and the mind, which senses ideas); we like sense pleasures and just like an animal being fed, we will identify with them and get stressed when they're taken away, like a baby crying when you take away its toy. While it's admirable to recognise thath sense pleasures don't lead anywhere, that mere recognition (rather than the recognition that the pleasures are non-self and impermanent) won't stop the strong hedonistic component of most peoples' minds.

I hope I'm not coming from the wrong angle, I just want to offer my thoughts on egoism.

Then what is your solution?
Balanced selflessness?
Zen enlightenment of the self by embracing the absence of self?
There's an entire branch of zen that studies beauty and peace within the void and the idea of "zero" and "absence" but we would be entering…rather abstract, somewhat spiritual territory.

In fact traditional Buddhist practice is about recognising that every phenomenon is "empty of self, impermanent and thus stressful". Really I don't have a solution for suffering (unless you're willing to go down a "spiritual" route), but there is advice: to not cling to your sense of self, to recognise everything you see, taste, smell, hear, think of as ultimately decaying, with no unchanging inner core that will be with you forever (as lovers would say, "I'll be with you forever" is only entertaining this delusion, appealing to our natural tendency to wish everything were constant).

If you only recognise that fact, you have a lot less suffering in your life. Anecdotally (I don't know if empirically or scientifically), various meditation practices (which can be entirely 'secular' in nature) help with this. Vipassana is especially useful.

So I don't have a way of organising society (except the usual socialism or anarcho-communism) but I am sure that the best way to do it is you take a step back and seeing things for what they really are, not with delusion. Praise and blame alike are just sounds, your body is not "yours", and any suffering is caused by attachment to objects, yourself or other people. Protect your mind from being assailed by your senses.

I'm not trying to convert you or inject you with any spiritual dogma or rubbish. Just saying, this realisation is what's helped me significantly. I hope it's not too personal.

I control something, because somehow I'm able to wipe my own ass each day.

Why? I like my own body and want to take care of it?

You're confusing what Stirner means by ego with the fixed idea of the self. The ego is merely the totality of being.

Spooks aren't just delusions, they're fixed ideas that demand your subjugation.