I feel confident that she was born to be a conqueror and a savior, but not a ruler.
Well it's certain at least one dragon will die. I mean, right now Dany is OP and needs a nerf. Suspense relies on enemies being on even playing grounds, and right now the scales are too tipped in her favor.
I'm thinking that all three will mostly die, followed by Dany. They'll probably die in the order their namesakes died, too. Rhaegal first, followed by Viserion and then Drogon.
Plus, one of GRRM's dedications is to Phyllis, thanking her "for making him put the dragons in." So the dragons weren't part of the original plot, and are probably somewhat expendable.
It seems anything or anyone with some magical abilities is a likely candidate to die. The show will probably end with some sort of radical change where there's a new world, one I assume will have no more magic in it by the end. Or the exact opposite, since in the beginning of the story magic was weak and mostly forgotten.
If the Targaryen line and their dragons were restored to power then that's not moving forward, but backward. It's one of the reasons I don't have hope for her story beyond being a savior.