A "good" ending can only happen if there is an option to not get hit with Soulkiller once you jack into Mikoshi. And the only option not to do that, is to commit suicide.
The original V dies, in every ending. And in some endings V's copy either goes to cyberspace, to be gobbled up by Alt, or goes back to their body, to die in 6 months.
The V that we start the game as, has no chance at survival. And that's lazy and bad writing and not worthy of an RPG that promised meaningful "choices".
True but it wouldn't be that hard to do. First Alt gives you the choice to get hit by soulkiller, instead of taking it on herself to just do it.
Secondly, if you choose not too, V is placed back into her body, into a medical coma, Hell the Emperor lived for decades in his sarcophagus V could live for a while longer in the same basic tech.
This you do a run with Panam and your romance option to find a piece of cyberwear that will stop the process and allow V to survive indefinitely in her body. Hell if the devs already made magic cyberwear in the Relic, they can make magic anti-Relic cyberwear.
Four V lives and decides whether to stay in NC and die in a blaze of glory, or go off with the Nomads and live a nice quiet peaceful life with their romance option.