im new so not sure but ive got some recommendations of people to check out, not really "pro choice" but certainly "anti existence", maybe some of these ideas will be interesting for you to integrate into your philosophy, they certainly helped me
hume - wrote an essay called "on suicide" writing against the christian tradition that labels it as sinful, but a lot of modern scholars read it as reasons where suicide can be morally permissible in certain situations, in his essay he attacks common pro life arguments such as a duty not to CTB due to god, society, and yourself, id recommend reading it
hegesias - argued that life is dominated by suffering and therefore death can be preferable, this is one of the most ancient pessimistic positions taken
the stoics - especially seneca and aurelius held the idea that suicide can be a rational decision if someone lives in circumstances which make it impossible to live a virtuous life, because life isnt an ultimate good, only virtue is
montaigne - treated suicide as something thats potentially legitimate and offered criticism against the idea that remaining alive is always obligatory
benatar - strong anti natalist, in his book "better to have never been at all" he argues that it is immoral to have children as it is unethical to bring people into a world where they are going to experience extreme suffering, people often argue that existence is good as we are able to get pleasure from it, but benatar argues that if you never exist, there is nobody being derived of pleasure, so it is good, he even argues that lives that are mostly good and peaceful still should not have come into existence
cabrera - another antinatalist, argues that being born leads people to experience extreme suffering (similar to benatar) but takes it a step further, by existing, we actively harm others, and this is the main problem of existing, you have needs, satisfying them interferes with other beings, causes them pain, so when you are brought into existence, you dont just cause yourself suffering, but all the people around you too
schopenhauer - semi against suicide surprisingly, sees it as giving into the "will to life" essentially this is the idea that underneath all conscious thoughts lies an irrational striving that constantly desires more and more, whenever you satisfy one desire, you will become bored, and want something else, life is an endless cycle of this, and is essentially want something > suffer from not having it > get it > get bored with it > want something else > repeat, hes against suicide because youre still giving into this "want" because he conclusdes that most suicidal people commit because they wish their life was different, but he is against the societal stigma against it, still, interesting stuff on the world, doesnt think CTB is wrong, jsut that it doesnt achieve the liberation youre after
mainlander - he takes schopenhauers pessimism and turns it into something more extreme, non existence is the ultimate preference, he believes that there was once a single deity (God) who somehow chose to cease existing, and the universe is what resulted from the suicide of the original deity, everything we see is the process in which original unity descends back into nothingness, for him, existence is essentially a detour on the way to non existence, and ultimate "goal" of existence is non existence, he thought that if humanity went extinct, it would be a form of redemption, he hung himself right after he published his work, because he felt complete after that
hartmann - every attempt to gain happiness is essentially an illusion, beneath reality, there lies the "unconscious", the universe becomes "conscious" of itself through human beings, and it eventually discovers "wait, existence isnt good" and so human beings have almost a moral duty to recognise how futile existence is, and conclude that non existence is futile, eventually leading to he end of existence
cioran - hes quite different from the others, hes asking the question of "why is there something rather than nothing? why was I dragged here without consent?" you suddenly find yourself alive > conscious > desiring > aging > suffering > knowing youre going to die, and you didnt ask for any of this, birth is almost like a catastrophe, he thinks its hard to justify why we exist, and its very strange, but he doesnt advocate for CTB, one of his quotes is that "there is no point killing yourself, because you'll always kill yourself too late" so instead it functions like an escape hatch, just knowing you can do it whenever is a tool for psychological freedom, even if you never use it
zapffe - argues that human consciousness has evolved far beyond what is necessary, were intelligent enough to realise were going to die, everything we build will disappear, suffering cant be avoided, etc, but evolution didnt give us a way to handle this knowledge, so we use "protective mechanisms" to avoid thinking about these things such as religion and connection to family
ligotti - inspired by zapffe, he believes that consciousness is a mistake of evolution, we are animals that evolved past the point of being able to recognise the horror that is nature, evolution doesnt care if were happy, it only wants us to endure and reproduce, so consciousness is essentially a trap, and he believes it would be better if the human race went extinct altogether
hope some of this helped, not all of it is specifically on suicide, but i think you can link it to it pretty well