There are ways to save Rose, it just depends on how you invest points.
I played through idk how many time and I can say I'm always intrigued!
The point system is pretty cool, it need some careful plannings and you don't actually need all of it for a "good" run but it's just not enough for you to complete every single scenarios and that's why it's so interesting.
Anyway, back to the topic, you CAN in fact save Rose and it's not mysterious about how. Merlindra, she's an annoying one but I'm pretty sure she was written supposingly to be annoying and it succeed but to me, she's not too annoying or unreasonable given the circumstances and what she is.
And tbh, Rose death isn't even a bad run, I like her and still prefer she stay alive but her death give way to another interesting story and more informations :3