Arrow Season 5 Finale: Predicting Who Lived And Who Died In 'Lian Yu'
2. No One
Then again, there's always the possibility that the showrunners pull a fast one on us, and don't actually kill anyone off (apart from Chase, obviously).
This bait-and-switch would be infuriating, but with everyone thinking at least a few characters will die, it'd be a surprising way of resolving things. Perhaps they got to the boat, maybe they're on the plane and using it as a raft, or quite possibly they're hiding out in the prison that previously housed Slade Wilson.
If everyone did survive it could well feel rather cheap, and like a total cheat, but it's a way of the show having its cake (blowing up the island, ensuring people come back) and eating it (not having to lose any characters).
Prediction: It'd be a risk, and the wrong choice, but not totally beyond possibility.