5. Joe West Will Die
We have a cop who's the main character's link to the police force, who happens to be the father of said main character's love interest. At times this sentence could describe either The Flash or Arrow. Joe's death would allow the spin-off series to move further away from the structure of its parent show, which could be worth doing so that nothing gets stale. That's not the only reason why it's likely Joe will die at some point. There have been several moments in the series already where he's looked rather vulnerable going up against metahumans, and he's had several near-death misses already. At some point he could easily not be so lucky, especially if he comes up against a villain looking to make things personal who knows his links to the Flash. It's conceivable that this could happen with either Captain Cold or Reverse-Flash onece they discover that connection and there are a couple of other super-powered bad guys who still have a bone to grind with Detective West. Parental figures don't seem to have the longest life expectancy in this universe, either, with both of Oliver Queen's parents dead and Barry Allen's mother having died before the show started. Killing off Joe would be in keeping with the writers' track record of shock deaths and as he's hugely likeable would deliver the feels that keep fans engaged with the show. All in all, it's not looking good for Joe.