WARNING: SPOILERS AHEAD!
With the tragic departure of Carter Hall a.k.a. Hawkman on [DC's Legends of Tomorrow](tag:2937021), we all have to wonder if any other main characters are going to die this season.
Assassin turned crimefighter turned corpse turned walking killing machine turned Legend, Sara has had a long journey so far on the Arrowverse. Seeing as the was just brought back from the dead early this season on Arrow, it just seems ludicrous to think she would die so soon afterwards
Rip Hunter is the one entity that brought this team together, and the one with the most to lose (well, technically already lost). He is logically the only one who would be able to experience the effects of Vandal Savages removal from the timeline, including the revival of his wife and child. Having him die would only be able to serve as a final push for the team to put aside their differences and band together, which Hawkman's death has already accomplished.
Jefferson Jackson and Martin Stein
Jax, being a new character, is essential to the Firestorm matrix, as well as, and let's be honest here, the racial diversity of the show. The death of the Ronnie Raymond character at the beginning of the season left a hole in the two man Firestorm team, and having it fall apart again so quickly would not be good for ratings or the plot. Having said that, Martin Stein will also probably stay alive for the same reasons, as the only way his death would make any sense is if Ronnie Raymond's character suddenly made a reappearance, which seems unlikely
Captain Cold and Heatwave
Leonard Snart's character has been growing so much since his introduction on The Flash, it would just make no sense to let him go as it would be a devastating blow. The same goes for Mick Rory, who, although he doesn't have the most screentime, has a great dynamic with Cold and is an essential to the Rogues Gallery
The Atom, ever since his first appearance on Arrow, has done much to capture the audiences attention. Looking at where the character is now, it can be seen that having so much to prove and his journey through his issues puts Ray at a place where it would be hard for him to be killed off.
This one's sort of a no-brainer. The main villain of the show, Vandal Savage, is Kendra's (im)mortal enemy. Having Carter die leaves Kendra as the only one able to kill Savage, and someone that important just cannot die.