In the comic, Nebula spends most of the story a prisoner of Thanos, being perpetually tormented, but eventually, she’s the one that actually gets the Infinity Gauntlet away from Thanos, and she uses it against him.
It certainly sounds like Nebula may see an arc that ends in more or less the same place in the movie.
Readers of the original Infinity Gauntlet comic may be perking up at this point, as (and this is your SPOILER WARNING if you don’t want to know what happens in the comics) Nebula actually has a fairly emotional explosion in the comic version of the story that the new movie will be based on.
Considering the path that her character has been on, it would certainly make sense, and it would make for a phenomenal moment on film.