All of the endings are certainly interesting. With the name and association you would expect the "Devil" ending to be the bad ending, or at least the evil one, yet tbh it's perfectly understandable why people would pick it: to avoid Soulkiller.
I don't really care for Soulkiller, so for me, Star has to be the best ending. Riding into the sunset with Panam (and potentially Judy for FemV), with a new family at your back is, for me, is the most fulfilling ending by far. Plus, I suspect V's condition is far from incurable (and the ending practically confirms it), so the ending for me is more sweet than bitter.
I was going to gloss over the importance of Soulkiller and just say "It's philosophical differences". But I think it needs to be expanded upon for people to understand why I don't have a problem with it.
You enter Mikoshi, boom zapped. At that moment there, V technically dies and is uploaded to Mikoshi. Alt then does some untangling and you have the option to renter your body. Now, the problem people have here is that the "soul" is supposedly not transferred along with the engram. This is further supported by what Alt states at the blackwall (though nobody should be trusting Alt to run a lemonade stand at this point).
From what I understand, a great many people's discomfort comes from the fact that they believe that V's "consciousness" or "soul" is lost in the transfer, in the same way that you can't guarantee that it's really "you" that wakes up every morning, or who comes out of a Star Trek teleporter. But, in my opinion, that's demonstrably not true, simply by the fact that you retain control over V. If you get zapped and it's just boom black screen roll credits (but V actually survives) that'd be interesting, but you control V through Mikoshi, and afterwards. Therefore, I would posit that you, as the player, actually forms the bond that links past V to future V (I.E her consciousness). It's meta asf.
Finally, to everyone around V, she is the same as before and after Mikoshi. Hell, she thinks she is the same. So, she is. Perceptibly there is no difference, so there isn't.
That's my take. Don't expect to convince you, but it's why I don't think Soulkiller being used on V is bad.