Captain America: Civil War sounds like it's going to be very excellent indeed, but it's be no means a dead lock. As bulletproof as its central premise is - the old brothers in arms turn against each other motif never really goes out of style - and, indeed, its principal characters appear to be, it's still vulnerable to a case of jumping the shark and sabotaging its own momentum just when things are starting to get very, very exciting.
The set-up - the Avengers are going to find themselves at the sharp end of a government enquiry as to whether they ought to maybe be held accountable for the widespread devastation they cause on a regular basis in the process of saving the world, with the gang fracturing over the issue - sounds solid enough, but there are a lot of mantraps waiting to clamp the legs of unsuspecting comic book sequels which aren't careful.
The tricky thing Civil War has to do is balance telling that thunderously portentous story with not stomping all over the big reveals and plot points which Infinity War. The two halves of Infinity War have to be the biggest and most extraordinary in the series yet, not least because with a name like Infinity War, thats kind of implied. Its an INFINITE WAR. WAR, FOREVER, IN EVERY PLACE IN SPACE AND TIME. Waiting For Godot, this aint.
Just FYI there are elements of this list which are pretty spectacularly spoilerific so mind out for that if youre a fan of not knowing stuff.