Batman, it has higher highs than every other franchise on this list and, save for Batman & Robin, hasn't fared too terribly on the weaker entries compared to other franchises on this list. X-Men has too many misses (The Last Stand, Origins: Wolverine and Dark Phoenix, even Apocalypse was just okay) to put it at the top. Spider-Man has comparable overall quality looking at each individual film in the franchise, but even it has a few whiffs (Spider-Man 3, both TASM movies) to keep it out of the top spot.