I see what you did there Im flattered that you would prefer to see her alive!
I will try to answer to everyone at once, but if you will feel I didn't answer to your point, feel free to poke me! (Just make sure you won't use sharp objects for poking and won't poke me through, unlike my characters I have only one clone! thanks~~)
First, about
killing her completely with all her clones. My thoughts about it has shifted that it won't be most possible solution, because she considers her clones as assets of the State, and will destroy them only if certain triggers will happen, mostly to prevent them from doing something, she won't want them to do. If she will blame herself, she will kill only herself without clones.
I see that you prefer point 5 (i.e. without suicide), it is not over yet, and she will act according to her beliefs and actions of peoples (and, maybe mostly, dev actors) around her. Although when her decisions will be random, I'll make sure, they will be more in the spirit of preventing her from dying.
About option 3(
loss of memory for the whole capsuleer period), I see there very different opinions. This was my idea to make some fun with her way before these events began to happen. I can lay it aside for a while, and, maybe, I will use it to revive her later after hitting option 1. Will she hold her current name, or will appear with her original name will depend on the physical condition of the character and account.
Now,
taking the tea. Indeed, she will prefer other means of dealing with herself, so for this option she would need someone to... akhem... 'help'. As for it being Korsavius, it will be a bit difficult, since he is not Caldari. But feasible. To 'feed' her with tea would be best when something will happen, that she cannot accept as is. For example, it could have been quite easy to feed her some tea right after she knew about Heth actually killed Yanala and tried to destroy whole Caldari Prime. Some time later, when she had some time to meditate on this (and lately she is just locked in her quarters without flying much, just thinking about things and trying to find explanations) and convince herself, it will be practically impossible. Although, she still doesn't have explanations for everything, and you could possible make her stumble, and if pull right ropes, make her to take the tea. Just remember, that she thinks like Caldari and using normal moral norms on her won't work. Oh, and also, she is veerrrry aggressive, so if you push her too hard, she will switch to attacking you instead
Arnulf, she is not Achura completely, so if someone will make a tea with a concentration enough to kill any Achura but pretty safe to other Caldari, just to test, if she really has Cadalri blood, or just deranged Achuran girl, she will survive it without problem.
Now back, to the most interesting and tricky part:
letting her live without suicide. First, I have said earlier, that she will remain loyal to the State in any case. To actually change it, make her (using Gottii's words) to throw rocks from outside, will be very difficult, almost impossible. At first, the war should stop (so she can't kill gallente), leadership changed, all her ideas devalued. But even in this case, she would prefer to simply kill herself, because "I won't be useful for the State anymore"-thing.
She would really prefer to not became "dissident scum" that she was fighting against, she despise greatly (and will continue to despise) those, who were opposing Heth, even if her own opinion of Heth will change radically. Going dissident is still feasible, but with very slim chance. It will be long and hard process, starting with her killing other enemies like sansha and pirating occasionally on "gallentes". But really, should the war stop, she will die.
So, well, the idea is, she will remain loyal to the State to the end, and if she will be throwing stones, it will be from the inside. At the same time she will try to maintain her convictions, and if her convictions will come to conflict to her loyalties, she must die, as proper Caldari. Well, there are two possibilities, that will change her convictions, but only in a small part: regarding Heth.
First: she will remain loyal to Heth even after his death and will idolize him, following line as Gottii said, just from inside the State. Probably at first she will be in a deep suicide-able condition, because she 'lost Heth' and 'can't live without him'. Probably she will suicide her current clone, probably not. But it is not fatal, since won't affect her other clones. But later, it will only reinforce her convictions, she will revere Heth as a hero and will be killing gallentes in his name, still keeping her in service of the State and following orders.
Second: if her attitude towards Heth will be reversed. This will depend mostly on following Heth's actions, and if his 'misdeeds' will overweight his 'merits' (in the sense of what he did to form her character and convictions), and possible for this she will have to review interpretation of his already completed actions, to drop them from 'merits' bowl to 'misdeeds'. In this case she at first will be in a very suicidal condition and it will be hard to prevent her from doing this, since she will believe she did a horrible mistake, that should be paid for with her blood. Eventually, she will enter state, suggested by Aria: "Why, yes, I used to be evil incarnate. I got better, though." She will continue to hate gallente (because it was way before Heth), she will remain in her service to the State, and will be killing gallente only because of pure hatred and duty. She will be ashamed of her past and loyalty to Heth.
Well, I think, that's all. Lets see how events will develop from here. And, Havohej, I like to pvp
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PS Diana doesn't want to 'kill Shin', some time later she won't want to kill either Kat or Arac as well, and will act on them with aggressive defense. She prefers to not have actual personal enemies according to her beliefs.
PPS Gottii, you are a bit freaky with this "you know my voice" thing, mmkay?
She is a soldier, not a showman.