Laurel has made great strides - perhaps too great, given how fast it has happened - in taking on the Black Canary mantle from her sister Sara, and as Laurel she has come a long way from the character so much of the fanbase despised in Seasons 1 and 2. She's a more natural fit now, and a less annoying one. Now that she has reached that stage, it'd be a cruel twist if she were the one to die. It does, however, fit with what we see at the gravestone from both Oliver and Barry (he's not exactly close to her, but would still be saddened by her death and there to support Oliver). However, they have already killed off one Black Canary/Lance sister, and though she'll be coming back it's for a different show. Would they really get rid of another Canary already?